DPOJET Printable Application Help

DPOJET
Jitter, Noise and Eye-diagram Analysis Solution
Printable Application Help
*P077004816*
077-0048-16
DPOJET
Jitter, Noise and Eye-diagram Analysis Solution
Printable Application Help
Supports DPOJET Software V1.0 and above
www.tektronix.com
077-0048-16
Copyright © Tektronix. All rights reserved. Licensed software products are owned by Tektronix or its subsidiaries
or suppliers, and are protected by national copyright laws and international treaty provisions. Tektronix products
are covered by U.S. and foreign patents, issued and pending. Information in this publication supersedes that in all
previously published material. Specifications and price change privileges reserved.
TEKTRONIX and TEK are registered trademarks of Tektronix, Inc.
Contacting Tektronix
Tektronix, Inc.
14150 SW Karl Braun Drive
P.O. Box 500
Beaverton, OR 97077
USA
For product information, sales, service, and technical support:
■
In North America, call 1-800-833-9200.
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Worldwide, visit www.tektronix.com to find contacts in your area.
Table of Contents
Welcome
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Introduction to the application
Free trials ........................................................................................................................................
Related documentation ...................................................................................................................
Conventions ....................................................................................................................................
Technical support ...........................................................................................................................
Customer feedback .........................................................................................................................
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Getting started
Product description .........................................................................................................................
DPOJET option levels ....................................................................................................................
Compatibility ..................................................................................................................................
Requirements and restrictions ........................................................................................................
Supported probes ............................................................................................................................
Installing the application ................................................................................................................
About DPOJET ...............................................................................................................................
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Operating basics
About basic operations .................................................................................................................
Starting the application ............................................................................................................
Application interface menu controls .......................................................................................
Virtual keypad .........................................................................................................................
Tips on DPOJET user interface ...............................................................................................
Basic oscilloscope functions .........................................................................................................
Application directories ............................................................................................................
File name extensions ...............................................................................................................
Application menu shortcuts .....................................................................................................
Returning to the application ....................................................................................................
Warning log notifiers ...............................................................................................................
Saving and recalling setups ..........................................................................................................
Saving a setup ..........................................................................................................................
Recalling a saved setup ...........................................................................................................
Recalling the default setup ......................................................................................................
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Table of Contents
Jitter, Noise and Eye-diagram analysis
About Jitter, Noise and Eye-diagram analysis ..............................................................................
Setting up DPOJET to take measurements ...................................................................................
Setting up the application for analysis ....................................................................................
Deskew for accurate measurement ..........................................................................................
Selecting a measurement .........................................................................................................
Table of measurements-Period/Freq .......................................................................................
Table of measurements-Jitter ..................................................................................................
Table of measurements-Noise .................................................................................................
Table of measurements-Time ..................................................................................................
Table of measurements-Eye ....................................................................................................
Table of measurements-Amplitude .........................................................................................
Table of measurements-Standard ............................................................................................
Test point selection in the standard tab ...................................................................................
Configuring measurements ...........................................................................................................
About configuring a measurement ..........................................................................................
General ....................................................................................................................................
Global ......................................................................................................................................
Filters .......................................................................................................................................
Clock recovery ........................................................................................................................
Bit config .................................................................................................................................
BER for PCI express measurements .......................................................................................
RJ-DJ .......................................................................................................................................
RN-DN ....................................................................................................................................
Bus state ..................................................................................................................................
Edges .......................................................................................................................................
SSC ........................................................................................................................................
General configuration (DPOJET) ...............................................................................................
One touch jitter ......................................................................................................................
Serial Data/Jitter guide ..........................................................................................................
Source configuration .............................................................................................................
Preferences setup ...................................................................................................................
Export data and measurement ...............................................................................................
Data logging ..........................................................................................................................
Sequencing ............................................................................................................................
Limits .....................................................................................................................................
Measurement summary .........................................................................................................
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Table of Contents
Results as statistics .....................................................................................................................
Viewing statistical results ......................................................................................................
Export results to ref waveform ..............................................................................................
Bit rate and pattern length detection ......................................................................................
Result as plots .............................................................................................................................
About plots ............................................................................................................................
Plot usage ..............................................................................................................................
Selecting plots .......................................................................................................................
Configuring plots ...................................................................................................................
Viewing plots ........................................................................................................................
Reports ........................................................................................................................................
About reports .........................................................................................................................
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Tutorial
Introduction to the tutorial ..........................................................................................................
Setting up the oscilloscope .........................................................................................................
Starting the application ...............................................................................................................
Waveform files ...........................................................................................................................
Recalling a waveform file ...........................................................................................................
Taking a period measurement .....................................................................................................
Taking a TIE measurement .........................................................................................................
Taking an eye height and width measurement ...........................................................................
Summary tutorial ........................................................................................................................
Stopping the tutorial ...................................................................................................................
Returning to the tutorial ..............................................................................................................
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Parameters
About parameters ........................................................................................................................
Measurement select parameters ..................................................................................................
Autoset parameters .....................................................................................................................
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Ref level menu parameters .........................................................................................................
Preferences parameters ...............................................................................................................
Deskew parameters .....................................................................................................................
Data logging parameters .............................................................................................................
Control panel parameters ............................................................................................................
Configure measurement parameters ...........................................................................................
Bit config parameters ............................................................................................................
Edges parameters ...................................................................................................................
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Table of Contents
Clock recovery parameters ....................................................................................................
SSC parameters .....................................................................................................................
RJ-DJ analysis parameters .....................................................................................................
RN-DN analysis parameters ..................................................................................................
Filters parameters ..................................................................................................................
Bus state ................................................................................................................................
General parameters ................................................................................................................
Global parameters ..................................................................................................................
Plots ............................................................................................................................................
Histogram plot parameters ....................................................................................................
Eye diagram plot parameters .................................................................................................
Spectrum plot parameters ......................................................................................................
Time trend plot parameters ....................................................................................................
Phase noise plot parameters ..................................................................................................
Bathtub plot parameters .........................................................................................................
Transfer function plot parameters .........................................................................................
Composite jitter histogram plot parameters ..........................................................................
Noise bathtub plot parameters ...............................................................................................
BER Eye contour plot paramters ...........................................................................................
Composite noise histogram plot parameters .........................................................................
BER Eye plot parameters ......................................................................................................
Correlated Eye plot parameters .............................................................................................
PDF Eye plot parameters .......................................................................................................
Reports ........................................................................................................................................
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Reference
Progress bar status messages ......................................................................................................
Breakdown of jitter (Jitter map) .................................................................................................
Breakdown of noise (Noise map) ...............................................................................................
Error codes ..................................................................................................................................
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Measurement range limit values .................................................................................................
Measurement units ......................................................................................................................
Custom mask file requirements ..................................................................................................
Correlation of measurement to configuration .............................................................................
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Algorithms
About algorithms
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Table of Contents
Period/Freq measurements .........................................................................................................
Period .....................................................................................................................................
Positive and negative width ...................................................................................................
Frequency ..............................................................................................................................
N-Period ................................................................................................................................
Positive and negative duty cycle ...........................................................................................
CC-Period ..............................................................................................................................
Positive and negative CC duty ..............................................................................................
Jitter measurements ....................................................................................................................
TIE .........................................................................................................................................
RJ ...........................................................................................................................................
RJ(h) ......................................................................................................................................
RJ(v) ......................................................................................................................................
Dual dirac random jitter ........................................................................................................
Jitter summary .......................................................................................................................
TJ@BER ................................................................................................................................
DJ ...........................................................................................................................................
Dual dirac deterministic jitter ................................................................................................
Phase noise ............................................................................................................................
PJ ...........................................................................................................................................
PJ(h) .......................................................................................................................................
PJ(v) .......................................................................................................................................
NPJ ........................................................................................................................................
DDJ ........................................................................................................................................
DCD .......................................................................................................................................
J2 ...........................................................................................................................................
J9 ...........................................................................................................................................
SRJ .........................................................................................................................................
F/N .........................................................................................................................................
Noise measurements ...................................................................................................................
TN@BER ..............................................................................................................................
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RN .........................................................................................................................................
RN(v) .....................................................................................................................................
RN(h) .....................................................................................................................................
DN .........................................................................................................................................
PN ..........................................................................................................................................
PN(v) .....................................................................................................................................
PN(h) .....................................................................................................................................
DDN(0) ..................................................................................................................................
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DDN(1) ..................................................................................................................................
DDN ......................................................................................................................................
NPN .......................................................................................................................................
Unit Amplitude ......................................................................................................................
Noise summary ......................................................................................................................
Timing measurements .................................................................................................................
Rise time ................................................................................................................................
Fall time .................................................................................................................................
Skew ......................................................................................................................................
High time ...............................................................................................................................
Low time ................................................................................................................................
Setup ......................................................................................................................................
Rise slew rate .........................................................................................................................
Fall slew rate .........................................................................................................................
Hold .......................................................................................................................................
SSC profile ............................................................................................................................
SSC MOD rate .......................................................................................................................
SSC FREQ DEV MIN ...........................................................................................................
SSC FREQ DEV MAX .........................................................................................................
SSC FREQ DEV ...................................................................................................................
tCMD-CMD ..........................................................................................................................
Time outside level .................................................................................................................
Eye diagram measurements ........................................................................................................
Eye width ...............................................................................................................................
Width@BER ..........................................................................................................................
Eye height ..............................................................................................................................
Height@BER .........................................................................................................................
Eye high .................................................................................................................................
Eye low ..................................................................................................................................
Q-factor .................................................................................................................................
Mask hits ...............................................................................................................................
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Autofit mask hits ...................................................................................................................
Amplitude measurements ...........................................................................................................
High .......................................................................................................................................
Low ........................................................................................................................................
DC common mode .................................................................................................................
AC common mode .................................................................................................................
T/nT ratio ...............................................................................................................................
High-Low ..............................................................................................................................
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DPOJET Printable Application Help
Table of Contents
V-Diff-Xovr ...........................................................................................................................
Overshoot ..............................................................................................................................
Undershoot ............................................................................................................................
Cycle max ..............................................................................................................................
Cycle min ..............................................................................................................................
Cycle Pk-Pk ...........................................................................................................................
Standard-Specific measurements ................................................................................................
DDR setup and hold measurements ......................................................................................
DDR Setup-SE ......................................................................................................................
DDR Setup-Diff ....................................................................................................................
DDR Hold-SE ........................................................................................................................
DDR Hold-Diff ......................................................................................................................
DDR tCL(avg)) ......................................................................................................................
DDR tCK(avg) ......................................................................................................................
DDR2 tDQSCK .....................................................................................................................
DDR tDQSQ-Diff ..................................................................................................................
DDR tDQSS ..........................................................................................................................
DDR tERR(n) and DDR tERR(m-n) .....................................................................................
DDR tHZDQ .........................................................................................................................
DDR tJIT(duty) .....................................................................................................................
DDR tJIT(per) .......................................................................................................................
DDR tLZDQ ..........................................................................................................................
DDR tCH(avg) ......................................................................................................................
DDR tRPRE ..........................................................................................................................
DDR tWPRE .........................................................................................................................
DDR tPST ..............................................................................................................................
DDR over area .......................................................................................................................
DDR under area .....................................................................................................................
DDR VID(ac) ........................................................................................................................
DDR3 Vix(ac) .......................................................................................................................
PCIe T-Tx-Diff-PP ................................................................................................................
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PCIe T-TX .............................................................................................................................
PCIe T-Tx-Fall ......................................................................................................................
PCIe Tmin-Pulse ...................................................................................................................
PCIe DeEmph ........................................................................................................................
PCIe T-Tx-Rise .....................................................................................................................
PCIe UI ..................................................................................................................................
PCIe Med-Mx-Jitter ..............................................................................................................
PCIe T-RF-Mismch ...............................................................................................................
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PCIe MAX-MIN ratio ...........................................................................................................
PCIe SSC PROFILE ..............................................................................................................
PCIe SSC FREQ DEV ..........................................................................................................
PCIe AC common mode ........................................................................................................
GDDR5 tBurst-CMD ............................................................................................................
GDDR5 tCKSRE ...................................................................................................................
GDDR5 tCKSRX ..................................................................................................................
T-TX-DDJ .............................................................................................................................
T-TX-UTJ ..............................................................................................................................
T-TX-UDJDD .......................................................................................................................
T-TX-UPW-TJ ......................................................................................................................
T-TX-UPW-DJDD ................................................................................................................
V-TX-EQ-NO ........................................................................................................................
V-TX-EIEOS .........................................................................................................................
ps21TX ..................................................................................................................................
V-Tx-Boost ............................................................................................................................
USB VTx-Diff-PP .................................................................................................................
USB TCdr-Slew-Max ............................................................................................................
USB Tmin-Pulse-Tj ...............................................................................................................
USB Tmin-Pulse-Dj ..............................................................................................................
USB SSC MOD RATE .........................................................................................................
USB SSC FREQ-DEV-MAX ................................................................................................
USB SSC FREQ-DEV-MIN .................................................................................................
USB SSC PROFILE ..............................................................................................................
USB UI ..................................................................................................................................
USB AC common mode ........................................................................................................
Jitter separation ...........................................................................................................................
Jitter analysis through RJ-DJ separation ...............................................................................
RJ-DJ separation via spectrum analysis ................................................................................
RJ-DJ separation for arbitrary patterns .................................................................................
Separation of Non-Periodic jitter (NPJ) ................................................................................
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Estimation of TJ@BER and eye Width@BER .....................................................................
Jitter estimation using Dual-Dirac models ............................................................................
Joint Jitter/Noise analysis ...........................................................................................................
Differences between Jitter-Only and Jitter+Noise analysis ..................................................
Use of Jitter+Noise analysis when DJAN is not enabled ......................................................
Basic steps in joint Jitter+Noise analysis ..............................................................................
Noise model component interrelationships ...........................................................................
Results ........................................................................................................................................
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Table of Contents
GPIB commands
About the GPIB program ............................................................................................................
GPIB reference materials ............................................................................................................
Argument types ...........................................................................................................................
DPOJET: ADDMeas ..................................................................................................................
DPOJET:APPLYAll ...................................................................................................................
DPOJET:BURSTConfig:BUS ....................................................................................................
DPOJET:BURSTConfig:CSACTIve ..........................................................................................
DPOJET:BURSTConfig:CSSource ............................................................................................
DPOJET:BURSTConfig:CUSTOMRate ....................................................................................
DPOJET:BURSTConfig:DATA ................................................................................................
DPOJET:BURSTConfig:DATARate .........................................................................................
DPOJET:BURSTConfig:DETECTMethod ................................................................................
DPOJET:BURSTConfig:GENERation ......................................................................................
DPOJET:BURSTConfig:LATEncy ............................................................................................
DPOJET:BURSTConfig:LENGth ..............................................................................................
DPOJET:BURSTConfig:SEARch ..............................................................................................
DPOJET:BURSTConfig:STRObe ..............................................................................................
DPOJET:BURSTConfig:TOLERance .......................................................................................
DPOJET:CLEARALLMeas .......................................................................................................
DPOJET:DESKEW ....................................................................................................................
DPOJET:DESKEW:DESKEWchannel ......................................................................................
DPOJET:DESKEW:DESKEWHysteresis ..................................................................................
DPOJET:DESKEW:DESKEWMidlevel ....................................................................................
DPOJET:DESKEW:EDGE ........................................................................................................
DPOJET:DESKEW:MAXimum ................................................................................................
DPOJET:DESKEW:MINimum ..................................................................................................
DPOJET:DESKEW:REFChannel ..............................................................................................
DPOJET:DESKEW:REFHysteresis ...........................................................................................
DPOJET:DESKEW:REFMidlevel .............................................................................................
DPOJET:DIRacmodel ................................................................................................................
DPOJET:EXPORT .....................................................................................................................
DPOJET:GATING .....................................................................................................................
DPOJET:HALTFreerunonlimfail ...............................................................................................
DPOJET:HIGHPerfrendering .....................................................................................................
DPOJET:INTERp .......................................................................................................................
DPOJET:JITtermode? ................................................................................................................
DPOJET:JITtermodel .................................................................................................................
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DPOJET:ANALYSISMETHOD ................................................................................................
DPOJET:LASTError? ................................................................................................................
DPOJET:LIMITRise ..................................................................................................................
DPOJET:MINBUJUI ..................................................................................................................
DPOJET:LIMits:FILEName ......................................................................................................
DPOJET:LIMits:STATE ............................................................................................................
DPOJET:LOGging:MEASurements:FOLDer ............................................................................
DPOJET:LOGging:MEASurements:STATE .............................................................................
DPOJET:LOGging:SNAPshot ...................................................................................................
DPOJET:LOGging:STATistics:FILEName ...............................................................................
DPOJET:LOGging:STATistics:STATE ....................................................................................
DPOJET:LOGging:WORSTcase:FOLDer .................................................................................
DPOJET:LOGging:WORSTcase:STATE ..................................................................................
DPOJET:MEAS<x> ...................................................................................................................
DPOJET:MEAS<x>:BER:TARGETBER .................................................................................
DPOJET:MEAS<x>:BITCfgmethod ..........................................................................................
DPOJET:MEAS<x>:BITPcnt ....................................................................................................
DPOJET:MEAS<x>:BITConfig:STARTPercent .......................................................................
DPOJET:MEAS<x>:BITConfig:ENDPercent ...........................................................................
DPOJET:MEAS<x>:BITConfig:NUMBins ...............................................................................
DPOJET:MEAS<x>:BITType ...................................................................................................
DPOJET:MEAS<x>:BUSState:CLOCKPolarity .......................................................................
DPOJET:MEAS<x>:BUSState:FROMPattern ..........................................................................
DPOJET:MEAS<x>:BUSState:FROMSymbol .........................................................................
DPOJET:MEAS<x>:BUSState:MEASUREType ......................................................................
DPOJET:MEAS<x>:BUSState:MEASUREFrom .....................................................................
DPOJET:MEAS<x>:BUSState:MEASURETO .........................................................................
DPOJET:MEAS<x>:BUSState:TOPattern ................................................................................
DPOJET:MEAS<x>:BUSState:TOSymbol ...............................................................................
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKBitrate ............................................................
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKFrequency ......................................................
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DPOJET:MEAS<x>:CLOCKRecovery:CLOCKMultiplier ......................................................
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKPath ...............................................................
DPOJET:MEAS<x>:CLOCKRecovery:DAMPing ...................................................................
DPOJET:MEAS<x>:CLOCKRecovery:DATARate ..................................................................
DPOJET:MEAS<x>:CLOCKRecovery:BWType .....................................................................
DPOJET:MEAS<x>:CLOCKRecovery:LOOPBandwidth ........................................................
DPOJET:MEAS<x>:CLOCKRecovery:MEANAUTOCalculate ..............................................
DPOJET:MEAS<x>:CLOCKRecovery:METHod .....................................................................
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DPOJET:MEAS<x>:CLOCKRecovery:MODel ........................................................................
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset .....................................................
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:AUTO? .......................................
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:MANual ......................................
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:Recalctype ..................................
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:SELECTIONtype ........................
DPOJET:MEAS<x>:CLOCKRecovery:PATTern .....................................................................
DPOJET:MEAS<x>:CLOCKRecovery:STAndard ...................................................................
DPOJET:MEAS<x>:COMMONMode:FILTers:STATE ..........................................................
DPOJET:MEAS<x>:CUSTomname ..........................................................................................
DPOJET:MEAS<x>:DATA? .....................................................................................................
DPOJET:MEAS<x>:DDR:MPERCycle ....................................................................................
DPOJET:MEAS<x>:DDR:NPERCycle .....................................................................................
DPOJET:MEAS<x>:DDR:WINDowsize ..................................................................................
DPOJET:MEAS<x>:EDGE1 .....................................................................................................
DPOJET:MEAS<x>:EDGE2 .....................................................................................................
DPOJET:MEAS<x>:EDGEIncre ...............................................................................................
DPOJET:MEAS<x>:EDGES:FROMLevel ...............................................................................
DPOJET:MEAS<x>:EDGES:LEVel .........................................................................................
DPOJET:MEAS<x>:EDGES:SLEWRATETechnique ..............................................................
DPOJET:MEAS<x>:EDGES:TOLevel ......................................................................................
DPOJET:MEAS<x>:FILTers:BLANKingtime ..........................................................................
DPOJET:MEAS<x>:FILTers:HIGHPass:FREQ .......................................................................
DPOJET:MEAS<x>:FILTers:HIGHPass:SPEC ........................................................................
DPOJET:MEAS<x>:FILTers:LOWPass:FREQ ........................................................................
DPOJET:MEAS<x>:FILTers:LOWPass:SPEC .........................................................................
DPOJET:MEAS<x>:REFVoltage ..............................................................................................
DPOJET:MEAS<x>:FILTers:RAMPtime .................................................................................
DPOJET:MEAS<x>:FROMedge ...............................................................................................
DPOJET:MEAS<x>:HIGHREFVoltage ....................................................................................
DPOJET:MEAS<x>:LOWREFVoltage .....................................................................................
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DPOJET:MEAS<x>:LOGging:MEASurements:FILEname? ....................................................
DPOJET:MEAS<x>:LOGging:MEASurements:SELect ...........................................................
DPOJET:MEAS<x>:LOGging:STATistics:SELect ..................................................................
DPOJET:MEAS<x>:LOGging:WORSTcase:SELect ................................................................
DPOJET:MEAS<x>:MASKfile .................................................................................................
DPOJET:MEAS<x>:MASKOffset:HORIzontal:SELECTIONtype ..........................................
DPOJET:MEAS<x>:MASKOffset:HORIzontal:AUTOfit? ......................................................
DPOJET:MEAS<x>:MASKOffset:HORIzontal:MANual ........................................................
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MEAS<x>:MEASRange ............................................................................................................
DPOJET:MEAS<x>:MEASRange:MAX ..................................................................................
DPOJET:MEAS<x>:MEASRange:MIN ....................................................................................
DPOJET:MEAS<x>:MEASRange:STATE ...............................................................................
DPOJET:MEAS<x>:MEASStart ...............................................................................................
DPOJET:MEAS<x>:N ...............................................................................................................
DPOJET:MEAS<x>:NAME? ....................................................................................................
DPOJET:MEAS<x>:PHASENoise:HIGHLimit ........................................................................
DPOJET:MEAS<x>:PHASENoise:LOWLimit .........................................................................
DPOJET:MEAS<x>:REFVoltage ..............................................................................................
DPOJET:MEAS<x>:RESULts? .................................................................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs? ................................................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:HITPopulation? .......................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:HITS? ......................................................................
DPOJET:MEAS<x>:RESULts:ALLacqs:LIMits:STATus? ......................................................
DPOJET:MEAS<x>:RESULts:ALLacqs:LIMits:HIgh:STATus? .............................................
DPOJET:MEAS<x>:RESULts:ALLacqs:LIMits:LOw:STATus? .............................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAX? .....................................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAXCC? ................................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAXCC:STATus? .................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAXHits? ...............................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAX:STATus? .......................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MEAN? ...................................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MEAN:STATus? ....................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MIN? .......................................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MINCC? .................................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MINCC:STATus? ...................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MINHits? ................................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:MIN:STATus? ........................................................
DPOJET:MEAS<x>:RESULts:ALLacqs:PK2PK? ...................................................................
DPOJET:MEAS<x>:RESULts:ALLacqs:PK2PK:STATus? .....................................................
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DPOJET:MEAS<x>:RESULts:ALLAcqs:POPUlation? ...........................................................
DPOJET:MEAS<x>:RESULts:ALLacqs:POPUlation:STATus? ..............................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:SEG(x):Hits? ...........................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:SEG(x):MAXHits? .................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:SEG(x):MINHits? ...................................................
DPOJET:MEAS<x>:RESULts:ALLAcqs:STDDev? ................................................................
DPOJET:MEAS<x>:RESULts:ALLacqs:STDDEV:STATus? .................................................
DPOJET:MEAS<x>:RESULts:CURRentacq:MAX? ................................................................
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Table of Contents
DPOJET:MEAS<x>:RESULts:CURRentacq:MAXCC? ...........................................................
DPOJET:MEAS<x>:RESULts:CURRentacq:MAXCC:STATus? ............................................
DPOJET:MEAS<x>:RESULts:CURRentacq:MAX:STATus? .................................................
DPOJET:MEAS<x>:RESULts:CURRentacq:MEAN? ..............................................................
DPOJET:MEAS<x>:RESULts:CURRentacq:MEAN:STATus? ...............................................
DPOJET:MEAS<x>:RESULts:CURRentacq:MIN? ..................................................................
DPOJET:MEAS<x>:RESULts:CURRentacq:MINCC? ............................................................
DPOJET:MEAS<x>:RESULts:CURRentacq:MINCC:STATus? .............................................
DPOJET:MEAS<x>:RESULts:CURRentacq:MIN:STATus? ...................................................
DPOJET:MEAS<x>:RESULts:CURRentacq:PK2PK? .............................................................
DPOJET:MEAS<x>:RESULts:CURRentacq:PK2PK:STATus? ..............................................
DPOJET:MEAS<x>:RESULts:CURRentacq:POPUlation? ......................................................
DPOJET:MEAS<x>:RESULts:CURRentacq:POPUlation:STATus? .......................................
DPOJET:MEAS<x>:RESULts:CURRentacq:STDDev? ...........................................................
DPOJET:MEAS<x>:RESULts:CURRentacq:STDDev:STATus? ............................................
DPOJET:MEAS<x>:RESULTS:STATus? ................................................................................
DPOJET:MEAS<x>:RESULts:VIew? .......................................................................................
DPOJET:MEAS<x>:RJDJ:BER ................................................................................................
DPOJET:MEAS<x>:RJDJ:DETECTPLEN ...............................................................................
DPOJET:MEAS<x>:RJDJ:PATLen ..........................................................................................
DPOJET:MEAS<x>:RJDJ:TYPe ...............................................................................................
DPOJET:MEAS<x>:RJDJ:WINDOwlength ..............................................................................
DPOJET:MEAS<x>:RNDN:BER ..............................................................................................
DPOJET:MEAS<x>:RNDN:AUTODETECTpattern ................................................................
DPOJET:MEAS<x>:RNDN:PATLen ........................................................................................
DPOJET:MEAS<x>:RNDN:TYPe ............................................................................................
DPOJET:MEAS<x>:RNDN:WINDOwlength ...........................................................................
DPOJET:MEAS<x>:SIGNALType ...........................................................................................
DPOJET:MEAS<x>:SOUrce1 ...................................................................................................
DPOJET:MEAS<x>:SOUrce2 ...................................................................................................
DPOJET:MEAS<x>:SSC:NOMinalfreq:AUTO? ......................................................................
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DPOJET:MEAS<x>:SSC:NOMinalfreq:MANual .....................................................................
DPOJET:MEAS<x>:SSC:NOMinalfreq:SELECTIONtype ......................................................
DPOJET:MEAS<x>:TIMEDATa? ............................................................................................
DPOJET:MEAS<x>:TOEdge ....................................................................................................
DPOJET:MEAS<x>:ZOOMEVENT .........................................................................................
DPOJET:NUMMeas? .................................................................................................................
DPOJET:ADDPlot ......................................................................................................................
DPOJET:CLEARALLPlots ........................................................................................................
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DPOJET:PLOT<x>:COMPOSITEJitterhist:VERTical:SCALE ................................................
DPOJET:PLOT<x>:COMPOSITEJitterhist:NUMBins .............................................................
DPOJET:PLOT<x>:COMPOSITEJitterhist:TJ .........................................................................
DPOJET:PLOT<x>:COMPOSITEJitterhist:RJNPJ ...................................................................
DPOJET:PLOT<x>:COMPOSITEJitterhist:PJ ..........................................................................
DPOJET:PLOT<x>:COMPOSITEJitterhist:DDJDCD ..............................................................
DPOJET:PLOT<x>:DATA:XDATa? ........................................................................................
DPOJET:PLOT<x>:DATA:XDATa:TJ? ...................................................................................
DPOJET:PLOT<x>:DATA:XDATa:RJBUJ? ............................................................................
DPOJET:PLOT<x>:DATA:XDATa:PJ? ...................................................................................
DPOJET:PLOT<x>:DATA:XDATa:DDJDCD? .......................................................................
DPOJET:PLOT<x>:DATA:XDATa:TN ....................................................................................
DPOJET:PLOT<x>:DATA:XDATa:RNNPN ...........................................................................
DPOJET:PLOT<x>:DATA:XDATa:PN ....................................................................................
DPOJET:PLOT<x>:DATA:XDATa:DDNZERO ......................................................................
DPOJET:PLOT<x>:DATA:XDATa:DDNONE ........................................................................
DPOJET:PLOT<x>:DATA:YDATa? ........................................................................................
DPOJET:PLOT<x>:DATA:YDATa:TJ? ...................................................................................
DPOJET:PLOT<x>:DATA:YDATa:RJBUJ? ............................................................................
DPOJET:PLOT<x>:DATA:YDATa:PJ? ...................................................................................
DPOJET:PLOT<x>:DATA:YDATa:DDJDCD? .......................................................................
DPOJET:PLOT<x>:DATA:YDATa:TN ....................................................................................
DPOJET:PLOT<x>:DATA:YDATa:RNNPN ...........................................................................
DPOJET:PLOT<x>:DATA:YDATa:PN ....................................................................................
DPOJET:PLOT<x>:DATA:YDATa:DDNONE ........................................................................
DPOJET:PLOT<x>:DATA:YDATa:DDNZERO ......................................................................
DPOJET:PLOT<x>:XUnits? ......................................................................................................
DPOJET:PLOT<x>:YUnits? ......................................................................................................
DPOJET:PLOT<x>:SOUrce? ....................................................................................................
DPOJET:PLOT<x>:TREND:TYPe ...........................................................................................
DPOJET:PLOT<x>:TYPe? ........................................................................................................
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DPOJET:PLOT<x>:BATHtub:BER ..........................................................................................
DPOJET:PLOT<x>:BATHtub:VERTical:SCALE ....................................................................
DPOJET:PLOT<x>:EYE:ALIGNment ......................................................................................
DPOJET:PLOT<x>:EYE:HORizontal:AUTOscale ...................................................................
DPOJET:PLOT<x>:EYE:HORizontal:RESolution ...................................................................
DPOJET:PLOT<x>:EYE:MASKfile .........................................................................................
DPOJET:PLOT<x>:EYE:STATE ..............................................................................................
DPOJET:PLOT<x>:EYE:SUPERImpose ..................................................................................
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DPOJET:PLOT<x>:HISTOgram:AUTOset ..............................................................................
DPOJET:PLOT<x>:HISTOgram:HORizontal:AUTOscale ......................................................
DPOJET:PLOT<x>:HISTOgram:HORizontal:CENter .............................................................
DPOJET:PLOT<x>:HISTOgram:HORizontal:SPAN ...............................................................
DPOJET:PLOT<x>:HISTOgram:NUMBins .............................................................................
DPOJET:PLOT<x>:HISTOgram:VERTical:SCALE ................................................................
DPOJET:PLOT<x>:PHASEnoise:BASEline .............................................................................
DPOJET:PLOT<x>:SPECtrum:BASE .......................................................................................
DPOJET:PLOT<x>:SPECtrum:HORizontal:SCALE ................................................................
DPOJET:PLOT<x>:SPECtrum:MODE .....................................................................................
DPOJET:PLOT<x>:SPECtrum:VERTical:SCALE ...................................................................
DPOJET:PLOT<x>:TRANSfer:DENominator ..........................................................................
DPOJET:PLOT<x>:TRANSfer:HORizontal:SCALE ...............................................................
DPOJET:PLOT<x>:TRANSfer:MODE .....................................................................................
DPOJET:PLOT<x>:TRANSfer:NUMerator ..............................................................................
DPOJET:PLOT<x>:TRANSfer:VERTical:SCALE ..................................................................
DPOJET:PLOT<x>:BERContour:ALIGNment .........................................................................
DPOJET:PLOT<x>:BERContour:HORizontal:AUTOscale ......................................................
DPOJET:PLOT<x>:BERContour:HORizontal:RESolution ......................................................
DPOJET:PLOT<x>:BERContour:MASK .................................................................................
DPOJET:PLOT<x>:BERContour:MASKFile ...........................................................................
DPOJET:PLOT<x>:BERContour:SUPERImpose .....................................................................
DPOJET:PLOT<x>:BERContour:BER1E6V ............................................................................
DPOJET:PLOT<x>:BERContour:BER1E9V ............................................................................
DPOJET:PLOT<x>:BERContour:BER1E12V ..........................................................................
DPOJET:PLOT<x>:BERContour:BER1E15V ..........................................................................
DPOJET:PLOT<x>:BERContour:BER1E18V ..........................................................................
DPOJET:PLOT<x>:BERContour:TARGETBER .....................................................................
DPOJET:PLOT<x>:VERTBATHtub:BER ................................................................................
DPOJET:PLOT<x>:VERTBATHtub:HORIzontal:SCALE ......................................................
DPOJET:PLOT<x>:CORRELATEDEye:BER1E6V ................................................................
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DPOJET:PLOT<x>:CORRELATEDEye:BER1E9V ................................................................
DPOJET:PLOT<x>:CORRELATEDEye:BER1E12V ..............................................................
DPOJET:PLOT<x>:CORRELATEDEye:BER1E15V ..............................................................
DPOJET:PLOT<x>:CORRELATEDEye:BER1E18V ..............................................................
DPOJET:PLOT<x>:CORRELATEDEye:TARGETBER ..........................................................
DPOJET:PLOT<x>:PDFEye:BER1E6V ...................................................................................
DPOJET:PLOT<x>:PDFEye:BER1E9V ...................................................................................
DPOJET:PLOT<x>:PDFEye:BER1E12V .................................................................................
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DPOJET:PLOT<x>:PDFEye:BER1E15V .................................................................................
DPOJET:PLOT<x>:PDFEye:BER1E18V .................................................................................
DPOJET:PLOT<x>:PDFEye:TARGETBER .............................................................................
DPOJET:PLOT<x>:BEREye:BER1E6V ...................................................................................
DPOJET:PLOT<x>:BEREye:BER1E9V ...................................................................................
DPOJET:PLOT<x>:BEREye:BER1E12V .................................................................................
DPOJET:PLOT<x>:BEREye:BER1E15V .................................................................................
DPOJET:PLOT<x>:BEREye:BER1E18V .................................................................................
DPOJET:PLOT<x>:BEREye:TARGETBER ............................................................................
DPOJET:PLOT<x>:COMPOSITENoisehist:HORIzontal:SCALE ...........................................
DPOJET:PLOT<x>:COMPOSITENoisehist:NUMBins ...........................................................
DPOJET:PLOT<x>:COMPOSITENoisehist:TN .......................................................................
DPOJET:PLOT<x>:COMPOSITENoisehist:RNNPN ...............................................................
DPOJET:PLOT<x>:COMPOSITENoisehist:PN .......................................................................
DPOJET:PLOT<x>:COMPOSITENoisehist:DDNZERO .........................................................
DPOJET:PLOT<x>:COMPOSITENoisehist:DDNONE ...........................................................
DPOJET:POPULATION:CONDition ........................................................................................
DPOJET:POPULATION:LIMIT ...............................................................................................
DPOJET:POPULATION:LIMITBY ..........................................................................................
DPOJET:POPULATION:STATE ..............................................................................................
DPOJET:QUALify:ACTIVE .....................................................................................................
DPOJET:QUALify:SOUrce .......................................................................................................
DPOJET:QUALify:STATE ........................................................................................................
DPOJET:REFLevel:CH<x>:MIDZero .......................................................................................
DPOJET:REFLevels:AUTOSet .................................................................................................
DPOJET:REFLevels:AUTOset:STATE? ...................................................................................
DPOJET:REFLevels:CH<x>:AUTOSet ....................................................................................
DPOJET:REFLevels:CH<x>:ABsolute .....................................................................................
DPOJET:REFLevels:CH<x>:ABsolute:RISEHigh ...................................................................
DPOJET:REFLevels:CH<x>:ABsolute:RISELow ....................................................................
DPOJET:REFLevels:CH<x>:ABsolute:RISEMid .....................................................................
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DPOJET:REFLevels:CH<x>:ABsolute:FALLHigh ..................................................................
DPOJET:REFLevels:CH<x>:ABsolute:FALLLow ...................................................................
DPOJET:REFLevels:CH<x>:ABsolute:FALLMid ...................................................................
DPOJET:REFLevels:CH<x>:ABsolute:HYSTeresis .................................................................
DPOJET:REFLevels:CH<x>:BASETop ....................................................................................
DPOJET:REFLevels:CH<x>:PERcent ......................................................................................
DPOJET:REFLevels:CH<x>:PERcent:FALLHigh ...................................................................
DPOJET:REFLevels:CH<x>:PERcent:FALLLow ....................................................................
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DPOJET:REFLevels:CH<x>:PERcent:FALLMid .....................................................................
DPOJET:REFLevels:CH<x>:PERcent:HYSTeresis ..................................................................
DPOJET:REFLevels:CH<x>:PERcent:RISEHigh .....................................................................
DPOJET:REFLevels:CH<x>:PERcent:RISELow .....................................................................
DPOJET:REFLevels:CH<x>:PERcent:RISEMid ......................................................................
DPOJET:REPORT .....................................................................................................................
DPOJET:REPORT:APPlicationconfig .......................................................................................
DPOJET:REPORT:AUTOincrement .........................................................................................
DPOJET:REPORT:COMments ..................................................................................................
DPOJET:REPORT:DETailedresults ..........................................................................................
DPOJET:REPORT:DISPunits ....................................................................................................
DPOJET:REPORT:ENABlecomments ......................................................................................
DPOJET:REPORT:PASSFailresults ..........................................................................................
DPOJET:REPORT:PLOTimages ...............................................................................................
DPOJET:REPORT:REPORTName ...........................................................................................
DPOJET:REPORT:SETupconfig ...............................................................................................
DPOJET:REPORT:SAVEWaveforms .......................................................................................
DPOJET:REPORT:STATE? ......................................................................................................
DPOJET:REPORT:VIEWreport ................................................................................................
DPOJET:RESULts:STATus? .....................................................................................................
DPOJET:RESULts:VIew ...........................................................................................................
DPOJET:SAVE ..........................................................................................................................
DPOJET:SOURCEAutoset ........................................................................................................
DPOJET:SOURCEAutoset:HORizontal:UICount .....................................................................
DPOJET:SOURCEAutoset:HORizontal:UIValue .....................................................................
DPOJET:SOURCEAutoset:STATE? .........................................................................................
DPOJET:STATE ........................................................................................................................
DPOJET:UNITType ...................................................................................................................
DPOJET:LOCKRJ ......................................................................................................................
DPOJET:LOCKRJValue ............................................................................................................
DPOJET:PLOT(x):BATHtub:XAXISUnits ...............................................................................
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DPOJET:PLOT(x):NOISEBATHtub:YAXISUnits ...................................................................
DPOJET:VERTUNITType ........................................................................................................
DPOJET:VERsion? ....................................................................................................................
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DPOJET Printable Application Help
Welcome
DPOJET is a jitter, noise, timing, and eye analysis tool for Tektronix
Performance Digital Oscilloscopes (DPO/MSO5000, DPO7000, DSA/DPO/
MSO70000 series). DPOJET enables you to achieve new levels of productivity,
efficiency, and measurement reliability on complex clock, digital, and serial data
signals. DPOJET revolutionized jitter analysis by adding noise analysis.
Some of the features of DPOJET are:
■
Advanced Jitter, Noise and Timing Analysis for clocks and data signals, with
up to 99 simultaneous measurements on 12 analog and 16 digital sources.
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Jitter Guide/Serial Data wizard for easy configuration of popular
measurement sets.
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One Touch Jitter wizard for quick jitter summaries.
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Accurate jitter decomposition and TJ (BER) estimation using industryaccepted methods.
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Isolate jitter and noise due to crosstalk, and make random and deterministic
estimations in the presence of crosstalk.
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Comprehensive measurement statistics.
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Random Jitter (RJ) Lock value for analysis.
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BER analysis of serial data rates.
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BUJ analysis of both clock and data signals.
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Flexible measurement/statistic logging and export capabilities.
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Sophisticated plots for graphical analysis such as Histograms, Time Trends,
Eye Diagrams, Spectrums, Bathtub Plots, BER Eye Contour, Composite
Jitter Histogram, Composite Noise Histogram, Noise Bathtub, BER eye,
Correlated Eye, PDF Eye and Real-Time Eye® diagrams with transition and
non-transition bit separation.
■
Tektronix patented Programmable PLL software clock recovery.
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Standards-specific support for clock recovery and jitter separation methods.
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Capture and storage of worst-case waveforms for subsequent analysis.
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Thorough remote programmability using oscilloscope-like syntax.
DPOJET Printable Application Help
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Welcome
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DPOJET Printable Application Help
Introduction to the application
Free trials
Refer to the Optional Applications Software on a Windows-Based Oscilloscope
Installation Manual for details on free trails which are available for all
applications. The manual is available on the Optional Applications Software on
Windows-Based Oscilloscopes DVD, in the documents directory.
NOTE. Before evaluating an application, first check that your DSA/DPO/MSO
series oscilloscope firmware version is consistent with the version requirements
mentioned in the application’s readme file. You can check the firmware version
number from the oscilloscope Help drop-down list (About TekScope). To check
the application's firmware compatibility, refer to the System Requirements
section of the readme.txt file.
If an application is introduced after you receive your oscilloscope, you can
download the application as described in the installation manual (Tektronix part
number 071-1888-XX) to obtain the free trial. Download the manuals from
www.tektronix.com/manuals and www.tektronix.com/software.
NOTE. Free trial is supported Via floating trial license.
DPOJET Printable Application Help
1
Introduction to the application
Related documentation
Tektronix manuals are available at: www.tektronix.com/manuals and
www.tektronix.com/software. Use the following table to determine the document
that you need:
Table 1: List of reference documents
For information on:
■
Operating the Oscilloscope
■
Software warranty
■
List of available applications
■
Compatible oscilloscopes
■
Relevant software and firmware version
numbers
■
Applying a new option key label
■
Installing an application
■
Enabling an application
■
Downloading updates from the Tektronix
Web site
Refer to:
Oscilloscope user manual.
Oscilloscope user online help.
Optional Applications Software on WindowsBased Oscilloscopes Installation Manual, which
is provided on the Optional Applications
Software on Windows-Based Oscilloscopes CDROM, in the Documents directory.
Conventions
Online Help uses the following conventions:
■
When steps require sequence of selections using the application interface, the
“>” delimiter marks each transition between a menu and an option. For
example, Analyze> Wizard > One Touch Jitter.
■
The terms “DPOJET application” and “application” refer to DPOJET.
■
The term “oscilloscope” refers to any product on which this application runs.
■
The term “DUT” is an abbreviation for Device Under Test.
■
The term “select” is a generic term that applies to the methods of choosing an
option: with a mouse or with the touch screen.
■
User interface screen graphics are taken from a DPO7000 series oscilloscope.
You can find a PDF (portable document format) file for this document in the
Documents directory on the Optional Applications Software on Windows-Based
Oscilloscopes DVD. The DVD booklet only contains information on installing
the application from the DVD and on how to apply a new label. You can also
find the PDF and the Online Help at Start>All Programs>TekApplications >
DPOJET.
2
DPOJET Printable Application Help
Introduction to the application
Table 2: Icon descriptions
Icon
Meaning
This icon identifies important information.
This icon identifies conditions or practices that could result in loss of data.
This icon identifies additional information that will help you use the
application more efficiently.
Technical support
Tektronix welcomes your comments about products and services. Contact
Tektronix through mail, telephone, or the Web site. Click Contacting Tektronix
for more information.
Tektronix also welcomes your feedback. Click Customer feedback for
suggestions for providing feedback to Tektronix.
Customer feedback
Tektronix values your feedback on our products. To help us serve you better,
please send us your suggestions, ideas, or other comments you may have
regarding the application or oscilloscope.
Direct your feedback via email to
techsupport@tektronix.com
Or FAX at (503) 627-5695, and include the following information:
DPOJET Printable Application Help
3
Introduction to the application
General Information
Application-specific
Information
■
Oscilloscope model number (for example, DPO/MSO5000, DPO7000, DSA/
DPO/MSO70000 series) and hardware options, if any.
■
Software version number.
■
Probes used.
■
Description of the problem such that technical support can duplicate the
problem.
■
If possible, save the oscilloscope and application setup files as .set and
associated .xml files.
■
If possible, save the waveform on which you are performing the
measurement as a .wfm file.
Once you have gathered this information, contact technical support by phone or
through e-mail. In the subject field, please indicate “DPOJET Problem” and
attach the .set, .xml and .wfm files to your e-mail. If there is any query related to
the actual measurement results, then you can generate a .mht report and send it.
The following items are important, but optional:
■
Your name
■
Your company
■
Your mailing address
■
Your phone number
■
Your FAX number
Enter your suggestion. Please be as specific as possible.
Please indicate if you would like to be contacted by Tektronix regarding your
suggestion or comments.
To include screen shots of the oscilloscope waveform and DPOJET user
interface, from your oscilloscope menu bar, click File > Save As > Screen
Capture. To include screenshots of the DPOJET plots, select the floppy-disk
icon from the plots toolbar. In either case, enter a file name in the Save As dialog
box, select an image file format (For example:.bmp or .png or .jpeg), choose a
save location and select Save. You can then attach the file(s) to your e-mail
(depending on the capabilities of your e-mail editor).
4
DPOJET Printable Application Help
Getting started
Product description
DPOJET is a jitter, noise, timing, and eye diagram analysis tool for Tektronix
Performance Digital Oscilloscopes (DPO7000/C, DSA/DPO70000/B/C, DSA/
DPO72504D, DSA/DPO73304D, MSO70000/C, DPO5000/B,
DPO72304/72504/73304DX, MSO72304/72504/73304DX and MSO5000/
B series). DPOJET enables you to achieve new levels of productivity, efficiency,
and measurement reliability on complex clock, digital, and serial data signals.
DPOJET answers the challenge with a jitter and noise breakdown extended to
properly classify the bounded uncorrelated disturbers in their own category,
increasing the accuracy of the jitter/noise result.
The application provides the following features:
■
One Touch Jitter Summary.
■
Measurement Setup Wizard.
■
Isolate jitter and noise due to crosstalk, and make random and deterministic
estimations in the presence of crosstalk.
■
Qualify the waveform measurement within a selected result range by
General.
■
Limit the waveform (data) analysis by Gating, applying a Qualifier or
configuring population limits.
■
High pass and low pass measurement filters.
■
Random Jitter (RJ) Lock value for analysis.
■
Auto-detection of signal type (clock or data), bit rate, and pattern length.
■
Different architectures for clock recovery to establish a reference clock, the
edges of which can be used as a basis for timing comparisons.
■
RJ-DJ and RN-DN decomposition on repeating and arbitrary data patterns.
■
BER analysis of serial data rates.
■
BUJ analysis of both clock and data signals.
■
Eye diagrams with transition and non-transition bits separation.
■
Show results as numeric and graphical displays.
■
Different types of two-dimensional display plots for easier analysis of results.
■
Automatic reference level autoset for eye diagrams, jitter, noise and timing
measurements.
■
Preferences shortcut to set up options available at the Select panel.
DPOJET Printable Application Help
5
Getting started
Jitter Analysis
Jitter Analysis is the measurement of Time Interval Error (TIE), advanced RJ-DJ
decomposition, and other clock to data edge relationships.
Noise Analysis
Noise Analysis is the set of measurements (RN, NN, DDN, ..) that are analogous
to Jitter component measurements (RJ, PJ, DDJ, ..).
Timing Analysis
Timing analysis is the measurement of period, setup, hold, skew, and other edgeto-edge data timing relationships.
Eye Diagram Analysis
Eye diagram analysis is the plotting and measurement of eye diagrams and
masks.
DPOJET option levels
The DPOJET application offers three different levels of features, depending on
how it is configured. The configurations are determined by the following order
codes:
■
DJE – Jitter and Eye Diagram Analysis Tools - Essentials
■
DJA – Jitter and Eye Diagram Analysis Tools - Advanced
■
DJAN – Noise Analysis Tools - Requires DJA
NOTE. The application name “Jitter and Eye Diagram Analysis Tools” is the
same for DJE, DJA. The application name for DJAN is "Noise Analysis Tools"
and it requires DJA enabled. However, Help > About DPOJET indicates the
configured option level. Save/Recall is compatible between the option levels. If a
setup file saved in DJA is recalled in DJE, only the capabilities available in DJE
will be recalled. If a setup file saved in DJAN is recalled in DJA or DJE, only the
capabilities available in DJA or DJE will be recalled.
6
DPOJET Printable Application Help
Getting started
Jitter and Eye Diagram
Analysis Tools Essentials
Use Essentials for basic timing and jitter analysis. Essentials offers:
■
Period, Frequency and Time Interval Error analysis.
■
Timing parametrics such as rise/fall times, pulse width and duty cycle.
■
Many graphical tools such as histograms, time trends, and spectrums.
■
Configurable HTML report generation.
■
Logging features for recording individual measurements, statistics, or worstcase waveforms.
■
Comprehensive remote control using oscilloscope-like GPIB syntax.
■
A wizard interface to ease common setup tasks.
NOTE. Summary View and Overall Test Result are not available for DJE.
Jitter and Eye Diagram
Analysis Tools-Advanced
The Advanced configuration offers all the features of Essentials, and adds the
following:
■
Jitter separation (RJ-DJ analysis).
■
Eye measurements.
■
Amplitude measurements.
■
Measurement filters.
■
Eye diagrams, bathtub plots or Mask Hits waveform plots.
■
Pass/Fail limits capability.
■
RJ Lock value
NOTE. Option DJA is required for PCI Express Gen1/Gen2/Gen3 measurements
and for DDRA measurements.
Noise Analysis Tools Requires DJA
The Noise Analysis Tools configuration offers all the features of Advanced and
adds the following:
■
Jitter separation RJ(h), RJ(v), PJ(h), PJ(v).
■
Noise measurements RN, RN(v), RN(h), DN, DDN, DDN(1), DDN(0), PN,
PN(v), PN(h), NPN, TN@BER, Unit Amplitude.
■
Plots related to composite Jitter+Noise analysis, such as BER Eye, Correlated
Eye and PDF Eye.
■
Noise measurement plots such as BER Eye contour, Noise Bathtub,
Composite Noise Histogram.
DPOJET Printable Application Help
7
Getting started
Compatibility
For information on oscilloscope compatibility, refer to the Optional Application
Software on Microsoft Windows Based Oscilloscopes Installation Manual,
Tektronix part number 077-0067-XX. The manual is available as a PDF file.
Requirements and restrictions
DPOJET requires Matlab MCR (Matlab Compiler Runtime) 8.0 for 64-bit
oscilloscopes. DPOJET requires .Net framework v4 or higher for 64-bit
oscilloscopes.
NOTE. MCR should be downloaded from www.mathworks.com if not available as
part of TekScope installation.
Supported probes
The application supports the following probes:
8
■
TAP1500
■
TAP2500
■
TAP3500
■
P5100
■
P6015
■
P6101A
■
P6139A
■
P6241
■
P6243
■
P6245
■
P6249
■
P6150
■
P6158
■
P7240
■
P7260
■
P7330
■
P7340A
■
P7350
■
P7350SMA
DPOJET Printable Application Help
Getting started
■
P7360A
■
P7380A
■
P7380SMA
■
P7313A
■
P7313SMA
■
All P75XX and P76XX probes
Installing the application
Refer to the Optional Applications Software on Windows-Based Oscilloscopes
Installation Manual for the following information:
■
Software warranty.
■
List of available applications, compatible oscilloscopes, and relevant
software and firmware version numbers.
■
Applying a new option installation key label.
■
Installing an application.
■
Enabling an application.
■
Downloading updates from the Tektronix Web site.
You can find a PDF (portable document format) file for this document in the
Documents directory on the Optional Applications Software on Windows-Based
Oscilloscopes DVD. The DVD booklet contains information on how to install the
application from the DVD and on how to apply a new option installation key
label.
About DPOJET
Click Help > About DPOJET to view application details such as the release
software version number, application name, and copyright.
DPOJET Printable Application Help
9
Getting started
NOTE. The version displayed above is indicative only, the version number
displayed will vary depending upon the exact version of the application installed.
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DPOJET Printable Application Help
Operating basics
About basic operations
Starting the application
Application interface
menu controls
On the oscilloscope menu bar, click Analyze>Jitter and Eye Analysis
(DPOJET) > Select to open the application.
Table 3: Application menu controls descriptions
Item
Description
Tab
Shortcut to a menu in the menu bar or a category of menu
options; most tabs are short cuts.
Area
Visual frame with a set of related options.
Option button
Button that defines a particular command or task.
Field
A box to type in text, or to enter a value with the Keypad or a
Multipurpose knob.
Check Boxes
Use to select or clear preferences.
Scroll bar
Vertical or horizontal bar at the side or bottom of a display area
that can be used for moving around in that area.
Browse
Displays a window where to look through a list of directories and
files.
Command button
Button that initiates an immediate action such as Run command
button
in the control panel.
Click to use on-screen keypad to enter alphanumeric values.
Virtual Keypad icon
MP knob references (a or b)
DPOJET Printable Application Help
Identifiers that show which Multi Purpose Knob (MPK) may be
used as an alternate means to control a parameter; turn the knob
on the oscilloscope front panel to adjust the corresponding
parameter Also, the value can be entered directly on the MPK
display component.
11
Operating basics
Virtual keypad
Tips on DPOJET user
interface
Select the
icon and use the virtual keypad to enter alphanumeric values, such
as reference voltage levels.
The following tips help you with the application user interface:
■
Use the Serial Data/Jitter Guide to rapidly set up and initiate sets of
commonly used measurements. After running the Serial Data/Jitter Guide,
you can modify the configuration parameters to meet specific needs.
■
Select a measurement to create a measurement and add it to the current
measurement table. New measurements initially use the same source as the
to change
earlier measurement, or the most recently used source. Click
the measurement source or adjust other source parameters such as the
reference levels.
12
■
Select any measurement multiple times to create multiple copies. This may
be useful if you wish to run the same measurement with different
configuration options.
■
to obtain a single set of measurements from a
Use the Single button
single new waveform acquisition. Pushing the button again before processing
has completed will interrupt the processing cycle.
■
to continuously acquire and accumulate
Use the Run button
measurements. Push the button again to interrupt the current acquisition.
■
Use the Recalc button
to perform measurements on the waveform
currently displayed on the oscilloscope, that is without performing a new
acquisition. This is useful if you wish to modify a configuration parameter
and re-run the measurements on the current waveform.
DPOJET Printable Application Help
Operating basics
Basic oscilloscope functions
Application directories
The installation directory for DPOJET is C:\Program Files\TekApplications
\DPOJET. During installation, the application sets up directories for various
functions such as to save setup files. The file name extension is used to identify
the file type.
Table 4: Application directories
1
Default directory
Used for
C:\%USERPROFILE%\Tektronix
\TekApplications\DPOJET\Images 1
Exported plot files.
C:\Users\Public\Tektronix\TekApplications
\DPOJET\Limits
Pass/fail limits files.
C:\Users\Public\Tektronix\TekApplications
\DPOJET\Patterns
Bit patterns.
C:\%USERPROFILE%\Tektronix
\TekApplications\DPOJET\Logs1
Log files. Consists of three subfolders:
■
Statistics for statistics log files (.csv)
■
Measurements for measurement log files
(.csv) and
■
Waveforms for worst case waveforms
(.wfm)
C:\Users\Public\Tektronix\TekApplications
\DPOJET\Masks
Mask files for various serial data standards. For
Example - PCIE, FBDIMM, SATA.
C:\%USERPROFILE%\Tektronix
\TekApplications\DPOJET\Reports1
Report files (.mht ).
C:\%USERPROFILE%\Tektronix
\TekApplications\DPOJET\Data1
Error log file, DPOJETErrors.log.
C:\Users\Public\Tektronix\TekApplications
\DPOJET\Examples
Various tutorial and support files.
%USERPROFILE% represents your user location.
DPOJET Printable Application Help
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Operating basics
File name extensions
Application menu
shortcuts
Table 5: File name extensions
File Extension
Description
.csv
Ascii file containing Comma Separated Values. This file format may be
read by any ascii text editor (such as Notepad) or may be imported into
spreadsheets such as Excel.
.xml
Ascii file containing measurement setup information, limits or other data
in Extensible Markup Language.
.set
Binary file containing oscilloscope setup information in a proprietary
format.
.mht
An HTML archive file, compatible with common Windows applications;
and contain the full report, including text and graphics.
.msk
A user mask file.
.wfm
Binary file containing an oscilloscope waveform record in a recallable,
proprietary format.
The DPOJET application provides shortcuts for navigating the user interface. Use
Alt+ A for the Analyze menu and Alt+A+J for Jitter and Eye Analysis
(DPOJET). Use Alt+A+E for PCI Express and Alt+A+U for USB 3.0 Essentials.
NOTE. is common for all submenus except the Help menu.
Table 6: Application shortcuts
Menu Items
SubMenu
Shortcut
Wizard
One Touch Jitter
Alt +A+J+J
Serial Data/Jitter Wizard
Alt +A+J+W
Select
Alt +A+J+S
Configure
Alt +A+J+C
Results
Alt +A+J+R
Plots
Alt +A+J+P
Reports
Alt +A+J+O
Export
Data Snapshot
Alt +A+J+E+D
Measurement Summary
Alt +A+J+E+S
Data Logging
Alt +A+J+L
Preferences
Alt +A+J+F
Limits
Alt +A+J+I
Global Configuration
Alt +A+J+G
Measurement Summary
Alt +A+J+M
Deskew
Alt +A+J+K
Help
About DPOJET
14
Alt +H+J
DPOJET Printable Application Help
Operating basics
Menu Items
Returning to the
application
Shortcut
Help on Jitter and Eye Analysis
Alt +H+T
Help on PCI Express MOI
Alt+H+M
Help on USB 3.0 MOI
Alt+H+U
When you access oscilloscope functions, the DPOJET control windows may be
replaced by the oscilloscope control windows or by the oscilloscope graticule.
Access oscilloscope functions in the following ways:
■
From the menu bar on the oscilloscope, choose Analyze > Jitter and Eye
Analysis (DPOJET) > Select.
■
Alternatively, switch between recently used control panels using the forward
or backward arrows
Warning log notifiers
SubMenu
on the right corner of the control panel.
Warning Log Notifiers display error messages or warnings. Warnings (
) or
Error (
) messages are also shown in the results tab. You can click View Log
to view the error log information in a text editor. Click OK to discard the
displayed error message.
You can set the duration for which the warning notification should appear on the
screen in the Preferences dialog box or click OK to discard the warning
information.
DPOJET Printable Application Help
15
Operating basics
NOTE. The error or warning log is saved as DPOJETErrors.log in subfolder,
where %USERPROFILE% represents your user location.
Saving and recalling setups
Saving a setup
The DPOJET application state is automatically saved with the oscilloscope state.
To save the oscilloscope settings and application state, follow these steps:
1. Click File>Save As >Setup.
2. In the file browser, select the directory to save the setup file.
3. Select or enter a file name. The application appends *_DPOJET.xml to store
DPOJET setup, and *.set to store oscilloscope settings.
4. Click Save.
NOTE. After the oscilloscope application is started, DPOJET needs to be
launched at least once before any saved DPOJET configuration can be recalled.
Recalling a saved setup
To recall the default application setup and oscilloscope settings, do the following
steps:
1. Click File > Recall.
2. Select the directory in the file browser to recall the setup file.
3. Select a .set file and click Recall.
NOTE. Only .set files can be selected for recall; any corresponding
_DPOJET.xml file in the same directory will be recalled as well, if DPOJET has
been launched at least once since the oscilloscope application was started. If
DPOJET has not been launched at least once, the oscilloscope settings will be
recalled but the DPOJET configuration will be ignored.
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DPOJET Printable Application Help
Operating basics
Recalling the default setup
To recall the default application and oscilloscope settings, click File>Recall
Default Setup.
DPOJET Printable Application Help
17
Operating basics
18
DPOJET Printable Application Help
Jitter, Noise and Eye-diagram analysis
About Jitter, Noise and Eye-diagram analysis
This section describes the DPOJET measurement and their analysis for real-time
oscilloscopes. Using Navigation panel and Control panel DPOJET measurements
are selected and analysed.
Control panel
The Control panel appears on the right of the application window. Using this
panel, you can start or stop the sequence of processes for the application and the
oscilloscope to acquire information from the waveform. The controls are Clear,
Recalc, Single and Run. The following table describes each of these controls:
Table 7: Control panel selections
Item
Description
Clear
Clears the current result display and resets any statistical results
and autoset ref levels.
Recalc
Runs the selected measurements on the current acquisition.
Single
Initiates a new acquisition and runs the selected measurements.
Run
Initiates a new acquisition and runs the selected measurements
repeatedly until Stop is clicked. Used only for live sources.
DPOJET Printable Application Help
19
Jitter, Noise and Eye-diagram analysis
Item
Description
Show Plots
Displays the plot summary window when clicked. This button
appears in the control panel only when a plot is selected.
DDR Analysis
Shortcut to access the DDRA application from DPOJET. Appears
in the control panel only when DDRA is opened using Analyze >
DDR Analysis.
The control panel with Show Plots is as shown:
Navigation panel
The Navigation panel appears on the left of the application window. It consists of
the following tabs: Select, Configure, Results, Plots and Reports.
Table 8: Navigation panel functions
20
Tab
Description
Select
Displays the various measurements available for selection. By
default, this tab is highlighted. You can click any measurement
categorized with Period/Freq, Jitter, Time, Eye and Amplitude
tabs.
Configure
Displays the configuration for the selected measurement.
Results
Displays the result for the selected measurement.
Plots
Displays the result as a two-dimensional plot for additional
measurement analysis. You can select and configure plots for
selected measurements.
Reports
Displays the configuration for generating reports in .mht format.
Allows you to select results, plots and details.
DPOJET Printable Application Help
Jitter, Noise and Eye-diagram analysis
Setting up DPOJET to take measurements
Setting up the application
for analysis
In general, setting up the application for analysis consists of these steps:
1. Selecting one or more measurements
2. Configuring parameters for the selected measurements
3. Configuring any global parameters
4. Adding plots to visual measurement results
Steps 2-4 are optional, and step 4 can be done either before or after measurement
results have been calculated. In addition to this manual process, several wizard
interfaces (One Touch Jitter, Serial Data/Jitter Guide) are available that can
streamline the process.
Selecting measurements is accomplished by first selecting a measurement
category (Period and Frequency, Jitter and Noise, Time, Eye, Amplitude, or
Standard-Specific Measurements) and then choosing specific measurements. A
measurement may be selected multiple times, for example to run on different
waveform sources or to run on the same waveform source with different
parameters.
Refer to the following sections for more details on various measurements:
Period and frequency measurements
Jitter measurements
Noise measurements
Time measurements
Eye measurements
Amplitude measurements
DPOJET Printable Application Help
21
Jitter, Noise and Eye-diagram analysis
Standard-specific Measurements
Related topics.
Selecting a measurement
Deskew for accurate measurement
Deskew for accurate
measurement
To ensure accurate results for two-channel measurements and differential signals
acquired on two channels, it is important to first deskew the probes and
oscilloscope channels before you take measurements of your DUT.
The application includes an automated deskew utility that you can use to deskew
any pair of oscilloscope channels.
NOTE. To produce the best deskew results, you should connect the probes to the
fastest slew rate signals from your DUT.
Connecting to a device under test (DUT). You can use any compatible probes or
cable interface to connect between your DUT and oscilloscope.
WARNING. To avoid electric shock, remove power from the DUT before
connecting the probes. Do not touch exposed conductors except with the properly
rated probe tips. Refer to the probe manual for proper use. Failure to do so may
cause injury or death.
Refer to the General Safety Summary in your oscilloscope manual.
Deskewing on Oscilloscopes with bandwidth extension. Some Tektronix
oscilloscopes feature software-based bandwidth extension. The bandwidth
extension may be enabled on a per-channel basis.
Enabling or disabling bandwidth extension on any channel affects the skew on
that channel. Thus, you should deskew probes and channels after you make such
configuration changes. Bandwidth Extension provides improved timing accuracy,
phase matching, and amplitude accuracy. It also will provide noise reduction.
Bandwidth extension should be used at all times.
22
DPOJET Printable Application Help
Jitter, Noise and Eye-diagram analysis
Steps to deskew probes and channels. To deskew probes and oscilloscope
channels, follow these steps:
1. Refer to Connecting to a Device Under Test before starting the procedure.
2. Connect both probes to the fastest signal in your DUT.
Set up the oscilloscope as follows:
1. Use the Horizontal Scale knob to set the oscilloscope to an acquisition rate so
that there is at least two, preferably five, samples per edge or more samples
on the deskew edge.
2. Use the Vertical Scale and Position knobs to adjust the signals to fill the
display without missing any part of the signals.
3. Set the Record Length so that there are more than 100 edges in the
acquisition.
4. Launch the DPOJET application.
5. Click Analyze > Jitter and Eye Analysis (DPOJET) > Deskew.
6. Set the Reference channel source to Ch1. The source waveform is the
reference point used to deskew the remaining channels.
7. Set the Channel to be Deskewed source as Ch2.
8. To start the process, click Perform Deskew.
9. Repeat steps 7 and 8 for other Ch waveforms.
10. Select Summary to view the deskew values.
DPOJET Printable Application Help
23
Jitter, Noise and Eye-diagram analysis
Deskew summary channel source and deskew values
Selecting a measurement
To take a measurement, click Analyze > Jitter and Eye Analysis (DPOJET) >
Select.
You can select measurements listed under the following categories:
■
Period/Freq: Click here to view the measurements grouped under Period/
Freq.
■
Jitter: Click here to view the measurements grouped under Jitter.
■
Noise: Click here to view the measurements grouped under Noise.
■
Time: Click here to view the measurements grouped under Time.
■
Eye: Click here to view the measurements grouped under Eye.
■
Amplitude: Click here to view the measurements grouped under Amplitude.
■
Standard: Click here to view the measurements grouped under Standard.
NOTE. Noise measurements are accessible only when DJAN - Noise Analysis
Tools is enabled.
■
When the Analysis Method is Jitter Only, Jitter tab is displayed and only
jitter measurements are accessible under Select panel. Click Analyze > Jitter
and Eye Analysis (DPOJET) > Preferences > Jitter Decomp to select the
analysis method as Jitter Only.
Figure 1: Jitter Only measurements are enabled
24
DPOJET Printable Application Help
Jitter, Noise and Eye-diagram analysis
■
When the Analysis Method is Jitter + Noise, Jitter tab will be displayed as
Jitter/Noise with measurements under Select panel. You can also see two
radio button for selecting Jitter or Noise measurements. By default Jitter
measurements are selected. Click Analyze > Jitter and Eye Analysis
(DPOJET) > Preferences > Jitter Decomp to select the analysis method as
Jitter + Noise.
Figure 2: Jitter/Noise measurements are enabled
NOTE. Preference setup - Jitter Decomp allows you to enable or disable Noise
measurements.
The application provides you different methods to set up the application:
Wizard
Wizard
■
The Serial Data/Jitter Guide allows you to set up, configure, and run the selected
set of measurements without requiring any knowledge of the control menus.
However, it does not provide access to many of the advanced features.
Measurement Setup sequence
Measurement setup sequence
■
The Measurement Setup Sequence buttons in the left navigation panel shows the
logical order you would follow to set up the application if you do not use the
Wizard.
Alternatively, click Analyze > [application name] to personalize DPOJET for a
specific standard. For example, to take a PCI Express measurement, click
Analyze > PCI Express and for USB 3.0 Essentials measurement, click Analyze
> USB 3.0 Essentials.
Related topics.
DPOJET option levels
DPOJET Printable Application Help
25
Jitter, Noise and Eye-diagram analysis
Table of measurementsPeriod/Freq
Definitions of the period and frequency-related measurements are given in the
following table:
Table 9: Period/Frequency measurements definitions
Table of measurementsJitter
Measurement
Description
Period
For clock signals, the elapsed time between consecutive crossings of the
mid reference voltage level in the direction specified; one measurement is
recorded per crossing pair. For data signals, the elapsed time between
consecutive crossings of the mid reference voltage in opposite directions
divided by the estimated number of unit intervals for that pair of
crossings; one measurement is recorded per unit interval so N
consecutive bits of the same polarity result in N identical period
measurements.
Frequency
The inverse of the period for each cycle or unit interval.
CC–Period
The cycle-to-cycle period; the difference in period measurements from
one cycle to the next, that is the first difference of the Period
measurement.
N–Period
The duration of N periods.
Pos Width
Amount of time the waveform remains above the mid reference voltage
level.
Neg Width
Amount of time the waveform remains below the mid reference voltage
level.
+Duty Cycle
The ratio of positive width to period, expressed in %.
–Duty Cycle
The ratio of negative width to period, expressed in %.
+CC–Duty
The difference between two consecutive positive widths.
–CC–Duty
The difference between two consecutive negative widths.
By default, the application enables analysis of all jitter components except nonperiodic jitter (NPJ). This is because NPJ (a form of bounded uncorrelated jitter
(BUJ) that isn’t periodic) is less frequently encountered and its analysis typically
requires longer waveforms, multiple waveforms, or both. The default processing
mode is called Spectral Only. To enable analysis of NPJ, you must set the
processing mode to Spectral + BUJ. This is done either from the PreferencesJitter Decomp panel or from the Jitter map.
Definitions of the jitter-related measurements are given in the following table.
NOTE. All jitter measurements except TIE are statistical measurements that
require sufficient record length so that all deterministic effects can be observed
and the random jitter can be modeled.
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DPOJET Printable Application Help
Jitter, Noise and Eye-diagram analysis
Table 10: Jitter measurements definitions
Measurement
Description
TIE
Time interval error is the difference in time between an edge in the
source waveform and the corresponding edge in a reference clock or
explicitly by another source signal. The reference clock is determined by
a clock recovery process.
RJ
Random jitter is the statistics for all timing errors not exhibiting
deterministic behavior, based on the assumption that they follow a
Gaussian distribution. If the Jitter separation model is set to Spectral +
BUJ, the Gaussian assumption is further validated and jitter appearing to
be non-Gaussian is excluded. Random jitter is characterized by its
standard deviation.
RJ–δδ
Dual-dirac random jitter is random jitter as defined above, but calculated
based on a simplified assumption that the histogram of all deterministic
jitter can modeled as a pair of equal-magnitude dirac functions (impulses
known as delta-functions).
DJ
Deterministic jitter is the statistics for all timing errors that follow
deterministic behavior. Deterministic jitter is characterized by its peak-topeak value.
DJ–δδ
Dual-dirac random jitter is random jitter as defined above, but calculated
on the same simplified model as described under RJ–δδ.
PJ
Periodic jitter is the statistics for that portion of the deterministic jitter
which is periodic, but for which the period is not correlated with any data
in the waveform.
DDJ
Data-dependent jitter is the statistics for that portion of the deterministic
jitter directly correlated with the data pattern in the waveform.
DCD
Duty cycle distortion is the statistics for that portion of the deterministic
jitter directly correlated with signal polarity, that is the difference in the
mean timing error on positive edges versus that on negative edges.
TJ@BER
Total jitter at a specified bit error rate (BER). This combines the random
and deterministic effects, and predicts a peak-to-peak jitter that will only
be exceeded with a probability equal to the BER.
Jitter Summary
This is not an individual measurement but a convenience function.
Pressing this button automatically adds a set of eleven jitter-related
measurements with a single action. The measurements are: TIE, RJ, RJ–
δδ, DJ, DJ–δδ, PJ, SRJ, DDJ, DCD, TJ@BER, and Width@BER.
Phase Noise
The RMS magnitude for all integrated timing jitter falling between two
specified frequency limits. This measurement is only applicable for clock
signals.
NPJ
1
1
Non-Period Jitter is the statistics for that portion of the non-deterministic
jitter that has a bounded distribution. It is characterized by its dual-dirac
amplitude (that is, the amount by which its presence causes an additional
separation of the two Gaussian distributions in the dual-dirac model).
The NPJ measurement is only available when the Jitter Separation Model is set to Spectral + BUJ under DPOJET
Preferences Setup.
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Jitter, Noise and Eye-diagram analysis
Measurement
Description
J2
Total jitter at a bit error rate (BER) value of 2.5E-3. This statistical value
predicts a peak-to-peak jitter that will only be exceeded with a probability
equal to the BER.
J9
Total jitter at a bit error rate (BER) value of 2.5E-10. This statistical value
predicts a peak-to-peak jitter that will only be exceeded with a probability
equal to the BER.
F/N
The peak-to-peak amplitude of periodic jitter occurring at a rate that
divides the data rate by an integer. (When a deterministic jitter
component could be interpreted either as F/N or DDJ, it is treated as DDJ
by convention.)
SRJ
Sub-rate jitter is jitter at rates that integrally divide the data rate. SRJ
typically results when a data stream has been created by multiplexing
multiple lower-rate streams. SRJ is a subcomponent of PJ, and can be
further isolated into F/N components.
RJ(h)
RJ(h) is that component of measured RJ which is due to direct phase
modulation.
RJ(v)
RJ(v) is that component of measured RJ which is due to vertical
waveform fluctuations, appearing as phase fluctuations due to AM-to-PM
conversion on the waveform rising or falling edges.
PJ(h)
PJ(h) is that component of measured PJ which is due to direct phase
modulation.
PJ(v)
PJ(v) is that component of measured PJ which is due to vertical
waveform fluctuations, appearing as phase fluctuations due to AM-to-PM
conversion on the waveform rising or falling edges.
Related topics.
Breakdown of jitter (Jitter map)
Preferences jitter decomp
Table of measurementsNoise
When DPOJET application is first launched, the noise analysis is disabled and no
noise measurements appear for selection. To enable noise measurements, click
Preferences > Jitter Decomp and select the Analysis Method as Jitter + Noise.
This option will not appear unless your scope has the optional Jitter + Noise
package (DJAN).
The application doesn't attempt to detect non-periodic Bounded Uncorrelated
Noise (NPN). This is because NPN is less frequently encountered and its analysis
typically requires longer waveforms, multiple waveforms, or both. The default
processing mode is called Spectral Only. To enable analysis of NPN, you must
set the processing mode to Spectral + BUJ. This is done either from the
Preferences jitter decomp panel or from the Noise map. The following table
describes the measurements under Noise.
28
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Table 11: Noise measurements definitions
Measurement
Description
RN
Random noise (RN) is the RMS magnitude of all non-deterministic
Gaussian-distributed vertical deviations from the nominal bit amplitude at
the specified UI offset of each bit interval.
RN(v)
RN(v) is that component of measured RN which is due to direct amplitude
modulation.
RN(h)
RN(h) is that component of measured RN which is due to phase
modulation, appearing as noise fluctuations due to PM-to-AM conversion
near the center of the unit interval.
DN
Deterministic noise (DN) is the peak-to-peak amplitude for all amplitude
variations from nominal bit amplitudes that exhibit deterministic (nonrandom) behavior.
DDN
Data dependent noise (DDN) is the total vertical eye closure due to bit
pattern-correlated vertical variations, at the center of the eye. It is the
sum of the positive peak DDN(0) relative to the nominal low level, and the
negative peak DDN(1) relative to the nominal high level.
DDN(0)
Data dependent noise 0 (DDN0) is the peak-to-peak amplitude for all bit
pattern-correlated vertical variations of low bits from the nominal low
level, at the specified UI offset.
DDN(1)
Data dependent noise 1 (DDN1) is the peak-to-peak amplitude for all bit
pattern-correlated vertical variations of high bits from the nominal high
level, at the specified UI offset.
PN
Periodic noise (PN) is the peak-to-peak amplitude for that portion of the
deterministic noise which is periodic, but for which the period is not
correlated with any data pattern in the waveform.
PN(v)
PN(v) is that component of measured PN which is due to direct amplitude
modulation.
PN(h)
PN(h) is that component of measured PN which is due to phase
modulation, appearing as noise fluctuations due to PM-to-AM conversion
near the center of the unit interval.
NPN
2
TN@BER
2
Non-Periodic noise (NPN) is the dual-dirac magnitude of that portion of
the bounded uncorrelated noise that is not periodic. Bounded
uncorrelated noise (BUN) is the collection of amplitude variations that is
not correlated to data pattern but which is bounded in vertical amplitude
(i.e. does not grow larger as the observation interval is increased). BUN
is composed of PN plus NPN.
Total noise at a specified bit error rate (BER). This extrapolated value
statistically predicts a peak-to-peak vertical eye closure (at the specified
horizontal bit offset) that will only be exceeded with a probability equal to
the BER. It is typically not equal to the actual vertical eye closure for a
given observation interval.
The NPN measurement is only available when the Jitter Separation Model is set to Spectral + BUJ under DPOJET
Preferences Setup.
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Jitter, Noise and Eye-diagram analysis
Measurement
Description
Unit Amplitude
Unit Amplitude is the difference between nominal high and low values,
and it is used to normalize all the other noise measurements if the units
are switched from absolute to normalized. The nominal high level is the
mean value of the distribution that represents DDN(1), and the nominal
low level is the mean value of the distribution that represents DDN(0).
Noise Summary
This is not an individual measurement but a convenience function.
Pressing this button automatically adds a set of nine noise-related
measurements with a single action. The measurements are: RN, DN, PN,
DDN, DDN0, DDN1, TN@BER and NPN2.
Related topics.
Breakdown of noise (Noise map)
Preferences jitter decomp
Table of measurementsTime
Definitions of the time-related measurements are given in the following table:
Table 12: Time measurements definitions
3
30
Measurement
Description
Rise Time
Elapsed time between the Low reference level crossing and the High
reference level crossing on the rising edge of the waveform
Fall Time
Elapsed time between the High reference level crossing and the Low
reference level crossing on the falling edge of the waveform
High Time
Amount of time the waveform remains above the high reference voltage
level
Low Time
Amount of time the waveform remains below the low reference voltage
level
Setup 3
Elapsed time between the designated edge of a data waveform and that
of a clock waveform, based on the respective mid reference level
crossings
Hold3
Elapsed time between the designated edge of a clock waveform and that
of a data waveform, based on the respective mid reference level
crossings
Rise Slew Rate
Rate of change of voltage between the two chosen reference level
crossings on the rising edges of the waveform
Fall Slew Rate
Rate of change of voltage between the two chosen reference level
crossings on the falling edges of the waveform
Skew3
Time difference between two similar edges on two waveforms assuming
that every edge in one waveform has a corresponding edge (either the
same or opposite polarity) in the other waveform; edge locations are
determined by the mid reference voltage level.
Two Source Measurements.
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Measurement
Description
SSC Profile
SSC Profile is not intended to serve as a measurement. It is a vehicle for
showing the SSC modulation profile versus time, using a time trend plot.
SSC Mod Rate
SSC Mod Rate computes the SSC modulating frequency.
SSC Freq Dev
SSC frequency deviation in ppm (parts per million), measured at each
inflection point in the modulation profile
SSC Freq Dev Min
The minimum frequency shift as a function of time
SSC Freq Dev Max
The maximum frequency shift as a function of time
Time Outside Level.
Time Outside Level Ring Back is defined as the time interval of overshoot
or undershoot.
tCMD-CMD
Table of measurementsEye
4
tCMD-CMD is a timing measurement and it measures the elapsed time
between two logic states on a specified digital bus.
Definitions of the eye-related measurements are given in the following table:
Table 13: Eye measurements definitions
4
Measurement
Description
Autofit Mask Hits
The number of unit intervals for which mask violations occurred. A mask
violation occurs when, during a unit interval, the waveform passes
through a segment of the defined mask. Autofit mask hits are separately
tailed for Segment 1 (upper), Segment 2 (Center) and Segment 3 (lower)
and the total for all three segments is also reported. Autofit Mask Hits
reports mask hits in terms of Pixel (not UI) and only the Segment
2 (Middle) is considered as criteria for mask hits calculation and it will
move the mask a location where the minimum or zero hits are happening.
Height
The measured clear vertical eye opening at the center of the unit interval.
Height = High(min) – Low(max)
Height@BER
The eye height at a specified Bit Error Rate
Width
Measured clear horizontal eye opening at the middle reference level.
Width = UI(mean) – TIE(max) – TIE(min)
Width@BER
The horizontal eye opening projected to correspond to a specified Bit
Error Rate. This number is obtained by measuring the jitter on the
waveform, performing RJ-DJ separation analysis, creating a bathtub
curve, and reporting the bathtub width at the appropriate error rate. This
eye width may not match the observed eye width because it is a
statistical measure. The measurement requires a sufficient record length
so that all deterministic effects can be observed and the random jitter can
be modeled.
Width(BER) = UI(mean) – TJ(BER)
This measurement is available only on 64-bit MSO instruments.
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Jitter, Noise and Eye-diagram analysis
Table of measurementsAmplitude
Measurement
Description
Mask Hits
The number of unit intervals for which mask violations occurred. A mask
violation occurs when, during a unit interval, the waveform passes
through a segment of the defined mask. Mask hits are separately tallied
for Segment 1 (upper), Segment 2 (center-of-eye mask) and Segment
3 (lower), and the total for all three segments is also reported. Thus, as
many as three hits can be added to the total count for each unit interval.
The population for this measurement gives the total number of unit
intervals observed.
Eye High
The voltage at a selected horizontal position across the unit interval, for
all High bits in the waveform.
Eye Low
The voltage at the selected horizontal position across the unit interval, for
all Low bits in the waveform.
Q-Factor
Quality Factor is the ratio of vertical eye opening to rms vertical noise.
Definitions of the amplitude-related measurements are given in the following
table:
Table 14: Amplitude measurements definitions
Measurement
Description
High
Vertical value in the central portion of the unit interval (UI) for high data
bits. The percent of the UI over which the waveform is evaluated is
adjustable, as is the method by which a single value is derived from this
span. The measurement may optionally be limited to transition or nontransition bits only.
Low
Vertical value in the central portion of the unit interval (UI) for low data
bits, with configuration options matching those of the High measurement.
High–Low
Difference between the mean value of the High measurement and the
mean value of the Low measurement.
DC Common Mode 5
Common-mode voltage for the two sources.
AC Common
5
32
Mode5
.
The common mode voltage between two single-ended signals. AC is
defined as all the frequency components above the cutoff frequency
(30 kHz).
T/nT-Ratio
Ratio of the transition eye-voltage to the nearest subsequent nontransition eye voltage, expressed in decibels.
V–Diff –Xovr 5
Voltage level at the crossover voltage of a differential signal pair.
Overshoot
Difference between the positive-going peak amplitude and the reference
voltage level, for each waveform event that exceeds the reference level.
Undershoot
Difference between the negative-going peak amplitude and the reference
voltage level (expressed as a positive number), for each waveform event
that exceeds the reference level.
Two Source Measurements.
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Table of measurementsStandard
Measurement
Description
Cycle Pk-Pk
Difference between the maximum and minimum voltage for each cycle,
where a cycle is defined as a positive half-cycle followed by a negative
half-cycle or a negative half-cycle followed by a positive half-cycle. Halfcycles are determined by the mid reference level crossings.
Cycle Min
Defined as the peak negative voltage for each negative half-cycle, where
half-cycles are determined by the mid reference level crossings.
Cycle Max
Defined as the peak positive voltage for each positive half-cycle, where
half-cycles are determined by the mid reference level crossings.
Standard-specific measurements in the this category may include timing, jitter,
amplitude or eye measurements. Generally, they are measurements that have
been modified to support a specific standard or otherwise deviate from the
generic measurements. Use the Standard drop-down list to view the DDR, PCI
Express and USB measurements. Use the Test point selection when available, to
select the setup file specific to the standard. Their measurement definitions are
given in the following table:
Table 15: Standard-specific measurements definitions
Measurement
Description
DDR
6
DDR Setup–SE 6
Elapsed time between the designated edge of a data waveform and that
of a single-ended DQS waveform, based on their respective DDR-specific
reference level crossings.
DDR Setup–Diff6
Elapsed time between the designated edge of a data waveform and that
of a differential DQS waveform, based on their respective DDR-specific
reference level crossings.
DDR Hold–SE6
Elapsed time between the designated edge of a single-ended DQS
waveform and that of a data waveform, based on their respective DDRspecific reference level crossings.
DDR Hold–Diff6
Elapsed time between the designated edge of a differential DQS
waveform and that of a data waveform, based on their respective DDRspecific reference level crossings.
DDR tCK(avg)
Calculated as the average clock period across a sliding N-cycle window.
DDR tCL(avg)
Defined as the average low pulse width calculated across a sliding Ncycle window.
DDR tCH(avg)
Defined as the average high pulse width and is calculated across a
sliding N-cycle window.
DDR tERR(n)
Defined as the cumulative error across multiple consecutive cycles from
tCK(avg).
DDR tERR(m-n)
Defined as the cumulative error across multiple consecutive predefined
cycles from tCK(avg).
Two Source Measurements.
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Jitter, Noise and Eye-diagram analysis
Measurement
Description
DDR tJIT(duty)
Defined as the cumulative set of the largest deviation of any single tCH
from tCH(avg) and the largest deviation of any single tCL from tCL(avg).
DDR tJIT(per)
Defined as the largest deviation of any single tCK from tCK(avg).
DDR tRPRE
Defined as the width of the READ preamble, from the exit of tristate to the
first rising edge on DQS.
DDR tWPRE
Defined as the width of WRITE preamble, from the exit of tristate to the
first rising edge on DQS.
DDR tPST
Defined as the width of the postamble, from the last falling mid reference
level crossing to the start of an undriven state (as judged by a rising trend
per JEDEC specs), for either a Read or Write burst.
DDR Over Area
Defined as the area of a triangle for which the base is defined by the
crossings of the configured reference level and the peak is the maximum
voltage level attained between those crossings.
DDR Under Area
Defined as the area of an inverted triangle for which the base is defined
by the crossings of the configured reference level and the (downward
pointing) peak is the minimum voltage level attained between those
crossings.
DDR VID(ac)
Defined as the AC differential input voltage.
DDR tDQSS6 7
WRITE command to 1st DQS latching transition.
DDR3 Vix(ac)
Defined as the differential input cross-point voltage relative to VDD/2 for
(CK/CK) or (DQS/DQS).
GDDR5 tBurst-CMD
87
Defined as the elapsed time from the last data element of a READ or
WRITE burst to the Command.
GDDR5 tCKSRE 87
Defined as the time elapsed from the SRE command to valid clock
cycles.
GDDR5 tCKSRX 87
Defined as the valid clock (CK) required before Self Refresh exit (SRX).
DDR2 tDQSCK
Defined as the elapsed time from the first rising DQS in a burst to the
nearest rising CK or CK#.
PCI Express
7
8
34
PCIe T-Tx-Diff-PP
Defined as the change in voltage level across a transition in the
waveform. It is the peak-to-peak differential voltage swing.
PCIe T-TX
Defined as the measured clear horizontal eye opening at the middle
reference level.
PCIe T-Tx-Fall
Defined as the time difference between the VRefLo(20%) reference level
crossing and the VRefHi(80%) reference level crossing on the falling
edge of the waveform.
PCIe Tmin-Pulse
Defined as the single pulse width measured from one transition center to
the next.
PCIe DeEmph
Defined as the ratio of the transition eye-voltage to the nearest
subsequent non-transition eye voltage, expressed in decibels.
Bus source is required.
This measurement is available only on 64-bit MSO instruments.
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Measurement
Description
PCIe T-Tx-Rise
Defined as the time difference between the VRefHi(80%) reference level
crossing and the VRefLo(20%) reference level crossing on the rising
edge of the waveform.
PCIe UI
For clock signals, the elapsed time between consecutive crossings of the
mid reference voltage level in the direction specified; one measurement is
recorded per crossing pair. For data signals, the elapsed time between
consecutive crossings of the mid reference voltage in opposite directions
divided by the estimated number of unit intervals for that pair of
crossings; one measurement is recorded per unit interval so N
consecutive bits of the same polarity result in N identical period
measurements.
PCIe Med-Mx-Jitter
Defined as the maximum time between the jitter median and the
maximum deviation from the median.
PCIe T-RF-Mismch
PCIe MAX-MIN Ratio
Defined as the mismatch between Rise time (TRise) and Fall time (TFall).
9
Defined as the voltage range ratio over which a particular receiver must
operate for consecutive UI.
PCIe SSC FREQ DEV Defined as the SSC frequency deviation in ppm (parts per million).
PCIe SSC PROFILE
Shows the modulation profile of the SSC.
PCIe AC Common
Mode6
The common mode voltage between two single-ended signals. AC is
defined as all the frequency components above the cutoff frequency
(30 kHz).
T-TX-DDJ
Defined as the time delta between the PDF’s mean for each zero
crossing point and the corresponding recovered clock edge.
T-TX-UTJ
Referenced to a recovered data clock generated by means of a CDR
tracking function. Uncorrelated total jitter may be derived after removing
the DDJ component from each PDF and combining the PDFs for all
edges in the pattern.
T-TX-UDJDD
Defined as uncorrelated jitter at the zero crossing point and the
corresponding recovered clock edge.
T-TX-UPW-TJ
Defined as an edge-to-edge phenomenon on consecutive edges.
T-TX-UPW-DJDD
Defined as uncorrelated PWJ at the zero crossing.
V-TX-NO-EQ
Defined by setting c-1 and c+1 to zero and measuring the p-p voltage on
the 64-ones/64-zeroes segment of the compliance pattern.
V-TX- EIEOS
Defined by setting c+1 coefficient value of –0.33 and a c-1 coefficient of
0.0 and measuring the p-p voltage on the 8-ones/8-zeroes segment of
the compliance pattern, where the pattern is repeated for a total of
128 UI.
ps21TX
Measured by comparing the 64-zeroes/64- ones p-p voltage (V111)
against a 1010 pattern (V101).
V-TX-BOOST
When c-1 and c+1 are non-zero, measure the PP voltage on the 64-ones/
64-zeroes segment of the compliance pattern and with immediate single
transition bit voltage.
USB 3.0 Essentials
9
Custom name for PCIe MAX-MIN Ratio is PCIe VRX-MAX-MIN Ratio.
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Jitter, Noise and Eye-diagram analysis
Measurement
Description
USB VTx-Diff-PP
Defined as the change in voltage level across a transition in the
waveform. It is the peak-to-peak differential voltage swing.
USB TCdr-Slew-Max 10 This measurement finds the peak-to-peak period jitter. Period jitter can be
obtained by taking the first difference of the filtered phase jitter.
USB Tmin-Pulse-Tj
Defined as the single pulse width measured from one transition center to
the next including all jitter sources.
USB Tmin-Pulse-Dj
Defined as the minimum pulse width with only deterministic jitter
components.
USB SSC MOD RATE Defined as the SSC modulation rate in terms of Hz.
USB SSC FREQ DEV Defined as the maximum frequency shift as a function of time.
MAX
USB SSC FREQ DEV Defined as the minimum frequency shift as a function of time.
MIN
Test point selection in the
standard tab
USB SSC PROFILE
Shows the modulation profile of the SSC.
USB UI
For clock signals, defined as he elapsed time between consecutive
crossings of the mid reference voltage level in the direction specified; one
measurement is recorded per crossing pair. For data signals, defined as
the elapsed time between consecutive crossings of the mid reference
voltage in opposite directions divided by the estimated number of unit
intervals for that pair of crossings; one measurement is recorded per unit
interval so that N consecutive bits of the same polarity result in N
identical period measurements.
USB AC Common
Mode6
The common mode voltage between two single-ended signals. AC is
defined as all the frequency components above the cutoff frequency
(30 kHz).
Test Point Selection is available only for PCI Express, USB, and MIPI standards.
You can either use the Test Point “Setup” button or File > Recall option to select
the setup file for the selected standard.
The Test Point shows “None Selected” if no test point is specified. Click Setup to
navigate to the directory, which contains the setup files specific to the standard.
The setup file with oscilloscope settings and test measurements replaces any
selected measurements and oscilloscope settings before specifying the test point.
A warning message is displayed as shown:
10
36
To run a slew rate measurement, you need a waveform with minimum record length of 5 MB.
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Once the test point is selected, the measurements associated with the test point
are displayed in the measurement table and the configuration specific to the
standard is recalled. However, you can still add the measurements specific to the
standard. At any time, you can save the setup file to recall. The Test Point field
displays only the Test point name. A tool tip displays the entire file name as
shown:
When you select PCI Express from the Standards list, a hint saying “This
standard contains Gen1 and Gen2 measurements” as shown:
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Jitter, Noise and Eye-diagram analysis
Configuring measurements
About configuring a
measurement
You can configure the measurements listed under the following categories:
■
Period/Freq
■
Jitter/Noise
■
Time
■
Eye
■
Amplitude
■
Standard
NOTE. Configuration for respective measurements are displayed only when
measurement is selected.
NOTE. When noise measurements are enabled, Jitter tab is displayed as Jitter/
Noise.
Related topics.
Correlation of measurement to configuration
Global
General
Filters
Clock recovery
Bit config
RJ-DJ
RN-DN
Configuring bus states
Edges
Spread spectrum clocking (SSC)
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General
Configuration tab allows you to customize the measurement name and qualify the
measurement within a selected result range. The General tab appears same for all
the measurements but is not common. The values are different for different
measurements. You can set the custom name per measurement here. Use the
virtual keyboard to enter the measurement name of your choice. Measurements
selected in DDRA are the custom names for the measurements defined in
DPOJET. A tool tip displays the custom name and the DPOJET-based
measurement name (in brackets) on moving the mouse over the row in the
measurement table, results, data snapshot, and measurement configuration
summary.
NOTE. Custom measurement names revert to their DPOJET-based measurement
names on being cleared in the General configuration screen.
Table 16: General options
Item
Description
Off
Disables the application from using the specified measurement limits.
On
Enables the application to use the specified measurement limits.
Max or Min value
Specify the maximum and minimum range of valid measurement values
measurements. The default values for the Measurement Range Limits
options vary by measurement.
Custom Measurement Option to modify the measurement name. Allows adding a user-specified
Name
name to any measurement. This is useful for aligning DPOJET
measurements with a user measurement list or standard.
NOTE. If a max value smaller than the min value is entered, it is accepted and the
min value is also silently reduced to the same value. Likewise, if a min value
larger than the max is entered, both are set to that value.
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Jitter, Noise and Eye-diagram analysis
Global
40
About global. This configuration tab is common for all measurements. You can
limit the waveform data analysis by Gating, by applying a Qualifier, or by setting
the measurement population limits. Access the Global configuration directly from
the oscilloscope menu under Analyze > Jitter and Eye Analysis (DPOJET) >
Global Configuration.
■
Gating
■
Qualify
■
Population
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Gating. Gating allows you to focus the analysis on a specific area of the
waveform bounded by a gated region, which is a way to filter unnecessary
information.
You can set up a gated region in one of the following ways:
■
Zoom
■
Cursors
Table 17: Global-Gating options
Item
Description
Off
No gating occurs; application takes measurements over the entire
waveform.
Zoom
Zooms the specified region of the source waveform to take
measurements within the selected area. The region of waveform within
the zoom is analyzed.
Cursors
Gates the waveform with Vertical cursors. The region of waveform within
the cursors is analyzed.
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41
Jitter, Noise and Eye-diagram analysis
Qualify. Qualifiers allows you to limit the application to more narrowly defined
conditions before taking measurements. All sources for the measurements and
Qualify input must have the same Horizontal Sample Rate, Record Length, and
Position to ensure that measurements function properly. For measurements which
require clock recovery such as TIE or eye measurements, only the first qualified
region will be measured even if multiple qualified regions are present. For all
other measurements, the entire waveform is processed.
Table 18: Global-Qualify options
42
Item
Description
Off
Disables the application from using the defined conditions while taking
measurements.
On
Enables the application to use the defined conditions while taking
measurements.
Configure
Displays the Qualify with logic dialog box.
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Configuring qualify with logic.
Table 19: Qualify-Configure options
Source
Ch1-Ch4, Ref1-Ref4, Math1-Math4 Search0-Search8
Configurati
on Panel
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Jitter, Noise and Eye-diagram analysis
Source
Ch1-Ch4, Ref1-Ref4, Math1-Math4 Search0-Search8
Configure Item
options
Source
Mid
Description
1
Selects a waveform to qualify the
signal or clock source used for the
measurement. The input source
waveforms or files are Ch1-Ch4,
Ref1-Ref4, and Math1-Math4.
Selects a waveform to qualify the
signal or clock source used for the
measurement. The input source
waveforms or files are Search0Search8. Displays the burst control
type selected in DDRA when you
turn on the qualifier. Also indicates
that ASM is turned on.
Shows the vertical reference level of
the qualifier waveform. 2
Hysteresis Shows the amount of hysteresis
applied to the vertical reference
level of the qualifier waveform.
Hysteresis prevents small amounts
of noise in a waveform from
producing multiple threshold
crossings.
Active
High13
Enables measurements in regions
where the qualifier waveform
exceeds the mid reference level.
3
Low13
Enables measurements in regions13
where the qualifier waveform falls
below the mid reference level.
OK
Accepts the changes and closes the
window.
Search behavior in DPOJET. When search is configured, the application analyzes
the identified marks on the source waveform. Read and Write bursts are selected
in ASM when search is selected as the qualify source. Each Mark indicates the
start and stop of a burst. These marks are used by the DPOJET measurement
when the qualify source is configured to Search. You can configure up to eight
searches (Search1 – Search8) in ASM (Advanced Search and Mark)and Search0
for visual search. The same search number gets reflected in DPOJET. Search is
used for Multiple burst analysis. For more details, refer to your oscilloscope
online help.
1
2
3
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Measurement and Qualify sources must have the same Horizontal Sample Rate, Record Length, and Position to ensure
that measurements function properly.
The default behavior for all reference levels is to automatically adjust based on the signal amplitude after a Clear
operation, unless you disable the autoset check box in the source configuration panel. Whether you use the Qualify
with Logic dialog box to adjust the levels or not, be aware that the levels may change if automatic adjustment is still
enabled. For more information, refer to Automatic versus manual reference voltage levels.
For measurements that require clock recovery, only the first qualified region will be measured even if multiple
qualified regions are present.
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Population. The Population control allows you to limit the amount of waveform
data that is analyzed. This is often done in industry standards to make sure that
there is consistency between measurement techniques.
Table 20: Global-Population options
Item
Description
Off
Disables the application from using a Population limit while taking
measurements.
On
Enables the application to use a Population limit while taking
measurements.
Configure
Displays the Population limit dialog box. This allows you to set a limit on a
maximum population to obtain, for selected measurements.
Configuring population limit.
Table 21: Population-Configure options
Item
Description
Population
The limit determines the population of measurement observations that
will be accumulated. Some measurements may accumulate observations
more quickly than others.
Acquisitions
The limit determines the number of acquisition cycles that will be
performed.
Each Measurement
Each measurement stops accumulating as soon as it reaches the
specified limit. Sequencing does not stop until all measurements have
reached the limit, at which time every measurement will have exactly the
limit.
Last Measurement
Sequencing continues and all measurements continue accumulating until
the last (slowest accumulating) measurement reaches the limit, at which
time they all stop. When sequencing stops, all measurements except one
may have higher population than the limit.
Limit
Specifies the number of acquisitions or measurements the application
takes before sequencing stops. Population limit is not applicable for Mask
Hits.
OK
Accepts the changes and closes the window.
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Filters
About filters. This configuration tab allows you to modify the measurement data
by applying a High Pass filter to block low frequency band components or a Low
Pass filter to block high frequency band components. For Example, Selecting a
1 MHz high pass filter can reduce the effect of SSC on results.
For some measurements (Period, Frequency, TIE, +Duty Cycle, –Duty Cycle,
+CC Duty, – CC Duty, CC–Period, Positive Width, Negative Width, N–Period,
Rise Time, Fall Time, Low Time, High Time, DC Common Mode, High–Low,
High, Low, T/nT Ratio, PCIe T-Tx-Rise, PCIe T-Tx-Fall, PCIe T-RF-Mismch,
PCIe UI, USB UI, PCIe SSC FREQ DEV, USB TCdr-Slew-Max, USB SSC
FREQ DEV, USB SSC MOD RATE and USB SSC PROFILE), the
measurements versus time waveform (time trend) that is derived from the
original oscilloscope waveform can be filtered before it is passed to the statistics
and plotting subsystems.
Band Pass Filtering. You can create a band pass filter by enabling both the High
Pass and the Low Pass filters on a measurement. The cut-off frequency for the
Low Pass filter must be greater than or equal to the cut-off frequency for the
High Pass filter.
You should be aware that setting the cut-off frequencies close to each other may
effectively filter out all of the measurement data, or all but a small amount of
timing noise. This diagram shows the spectrum of the measurement data passed
to the statistics and plotting subsystems when you use both the High Pass and the
Low Pass filters.
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High Pass filters attenuate low frequencies, and filter out DC values entirely.
When a high pass filter is added to a period or frequency measurement, the mean
value of the filtered measurement goes to zero. This can be seen by creating a
Time Trend plot of a high-pass-filtered period or frequency measurement.
Although this is the correct theoretical behavior for the filtered measurement, it is
not very useful if the Results panel reports that the mean period or frequency is
zero. For this reason, the mean values that appear in the results panels for Period
and Frequency measurements are the values before the filter.
Table 22: Filter options
Item
Description
Filter Spec
When enabled, blocks the low frequency band and passes only the high
frequency band of the waveform; defined as 1st order, 2nd order, 3rd order
Butterworth and No filter, being the default.
Freq (F1)
1
1
High Pass filter cut-off frequency at which the filter magnitude falls by
3 dB.
Filter Spec
When enabled, blocks the high frequency band and passes only the low
frequency band of the waveform; defined as 1st order, 2nd order, 3rd order
Butterworth, and No filter, being the default.
Freq (F2)14
Low Pass filter cut-off frequency at which the filter magnitude falls by
3 dB.
Advanced
Displays the Advanced filter configuration dialog box.
Apply to All
Settings of the measurement are applied to all measurements with those
settings.
Includes a 3 dB cut-off frequency.
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Measurements such as AC Common Mode, PCIe AC Common Mode, and USB
AC Common Mode use a high-pass sliding window filter. This filter is applied to
remove low frequency common mode noise. It has a 30 kHz cutoff frequency.
Table 23: Filter options
Item
Description
High Pass Frequency
Off
High pass frequency is set to Off. Default configuration of High pass
frequency for measurements is Off.
On
High pass frequency is set to On.
Brick wall filter configuration. Measurements such as PCIe DeEmph and PCIe
Med-Mx Jitter use the Brick Wall filter. A brick wall filter is applied to the PCIe
signal to remove the low frequency jitter components. The PCI Express
application applies the filter as per the PCIe specification. A Brick Wall filter has
a very sharp cut-off frequency.
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Advanced filter configuration. The measurement filters are implemented using
infinite impulse response (IIR) designs. As with any causal filter, a transient may
occur at the filter’s output in response to the arrival of the input signal. It is
usually desirable to exclude this transient from the measurement results.
In the DPOJET application, the filter transient is managed in two ways. First, the
input to the filter is gently “ramped up” from zero to its full value over some
ramp time tr. Second, the output of the ramp is “blanked” over some duration tb,
so that the remaining effects of any transient are omitted from measurement
results, statistics and plots. The sequence of operations is depicted here:
The ramp function has a raised-cosine profile and is defined in the time domain
as:
You may adjust the ramp time tr by means of the Advanced control panel. If you
wish to turn off the ramp function, set the ramp time to 0.
Similarly, you can adjust the blanking duration tb by means of the Advanced
control panel. Setting the blanking duration to 0 will allow you to see the entire
filtered measurement, including any transients.
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Both, the ramp time tr and the blanking duration tb, are set relative to the
reciprocal of the lowest filter frequency Fc. By default, both of these parameters
are set to 1/Fc. Since they are normalized to the filter frequency, they will
automatically adjust if you change the filter cut-off frequency.
The complete set of signal processing options, together with representative
waveforms that suggest how the options affect the measurement vector, are
shown here:
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Table 24: Advanced filter configuration options
Clock recovery
Item
Description
Ramp Time
Duration of the raised-cosine smoothing function applied to the
measurement vector before the vector is filtered.
Blanking Time
Duration of the filter’s output that is suppressed. The blanked portion of
the output is not included in the measurement statistics, or in any plots.
OK
Accepts changes and closes.
About clock recovery. Clock recovery refers to the process of establishing a
reference clock, the edges of which can be used as a basis for timing
comparisons. The Clock Recovery configuration tab allows you to select one of
the following clock recovery methods:
Constant Clock - Mean
Constant Clock - Median
Constant Clock - Fixed
Phase locked loop standard bandWidth
Phase locked loop custom bandWidth
Explicit Clock - Edge
Explicit Clock - PLL
The first five methods derive the reference clock from the same channel upon
which the measurement is defined. This is the conventional method of clock
recovery for serial data communications, where no separate clock is available.
The last two methods (Explicit Clock) derive the reference clock from a channel
other than the one upon which the measurement is defined.
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About constant clock recovery. In Constant Clock Recovery, the clock is assumed
to be of the form A*sin (2Π ft +Φ), where the frequency (f) and phase (Φ) are
treated as unknown constants. Once a source waveform has been acquired and the
edges extracted, one or both of these constants are determined using linear
regression, so that the recovered clock minimizes the mean squared sum of the
Time Interval Error (TIE) for that waveform.
If Constant Clock - Mean is selected as the clock recovery method, both the
frequency and the phase are chosen to minimize the mean squared error.
If Constant Clock - Fixed is selected as the clock recovery method, the precise
frequency specified is used but the phase is chosen so that the median error
between the recovered and measured edges is zero.
If Constant Clock - Median is selected as the clock recovery method, the phase is
chosen so that the median error between the recovered and measured edges is
zero.
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Constant clock - mean. This method provides the following options that control
how the clock recovery is performed:
■
Auto Calc First Acq
■
Auto Calc Every Acq
Selecting Autocalc First Acq will allow the clock-recovery algorithm to choose a
new best-fit clock frequency and phase only on the first acquisition. Subsequent
acquisitions will choose a best fit on clock phase but retain the clock frequency
found on the first acquisition.
Selecting Autocalc Every Acq will allow the clock-recovery algorithm to choose
a new best-fit clock frequency and phase for each new oscilloscope acquisition.
Clearing the measurement results by choosing Clear on the sequencing panel will
reset the clock recovery so that both frequency and phase are optimized on the
subsequent acquisition.
Table 25: Constant clock - mean options
Item
Description
Auto Calc First Acq
Calculates the best fit of the initial acquisition or the first acquisition after
clearing results, and then uses the value until you clear the results.
Auto Calc Every Acq
Calculates the best fit for each acquisition (default).
Apply to All
Apply
Applies the current clock recovery configuration to all selected
measurement(s), PLL-Standard clock recovery options that have Clock
Recovery as configuration tab.
Advanced
Displays the Clock recovery advanced setup dialog box.
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Constant clock - median. This method provides the following options that control
how the clock recovery is performed:
■
Auto Calc First Acq
■
Auto Calc Every Acq
Selecting Autocalc First Acq will allow the clock-recovery algorithm to choose a
new best-fit clock frequency and phase only on the first acquisition. Subsequent
acquisitions will choose a best fit on clock phase but retain the clock frequency
found on the first acquisition.
Selecting Autocalc Every Acq will allow the clock-recovery algorithm to choose
a new best-fit clock frequency and phase for each new oscilloscope acquisition.
Clearing the measurement results by choosing Clear on the sequencing panel will
reset the clock recovery so that both frequency and phase are optimized on the
subsequent acquisition.
Table 26: Constant clock - median options
Item
Description
Auto Calc First Acq
Calculates the best fit of the initial acquisition or the first acquisition after
clearing results, and then uses the value until you clear the results.
Auto Calc Every Acq
Calculates the best fit for each acquisition (default).
Apply to All
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Apply
Applies the current clock recovery configuration to all selected
measurement(s) that have Clock Recovery as the configuration tab.
Advanced
Displays the Clock recovery advanced setup dialog box.
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Constant clock - fixed. This method provides a single option that controls how the
clock recovery is performed. With Fixed Constant Clock recovery, no attempt is
made to derive information about the actual data rate from the signal under test.
Instead, the precise frequency that you specify will be used. (However, the clock
phase will be chosen so that the median difference between the recovered and
measured edges is zero.)
NOTE. Click to apply the clock recovery configuration to all selected
measurement(s) that have Clock Recovery as configuration tab.
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Clock recovery advanced setup. The Advanced Clock Recovery methods can be
used when unusually high noise or ambiguous data patterns defeats normal clock
recovery methods. Under most normal operating conditions, these methods are
not required nor recommended.
Nominal Data Rate and Known Data Pattern are the two advanced clock recovery
methods.
In Nominal Data Rate, you can provide the nominal data rate to the clock
recovery algorithm. Normally, the application analyzes your data and determines
the data rate automatically. Setting this parameter to Manual allows you to
provide a starting point or hint to the clock recovery algorithm. This is useful
when the data pattern makes data rate detection ambiguous. As an example, a
“1 1 0 0 1 1 0 0” pattern at 8 Gb/s would otherwise be detected as a “1 0 1 0”
pattern at 4 Gb/s. Setting the bit rate to 8 Gb/s will cause the proper unit interval
and pattern length to be identified.
In Known Data Pattern, the pattern is specified by using an ASCII text file
containing the characters 1 and 0. The file may contain other characters, spaces
and tabs for formatting purposes, but they will be ignored. Several files for
commonly used patterns are included with the application, and you may use these
as examples if you wish to create your own pattern files. Click Browse to modify
the default location for pattern files.
NOTE. The last line of the pattern file must end with a CR/LF. Without the CR/LF,
you will receive a too many bits error message.
Table 27: Advanced clock recovery options
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Item
Description
Auto
Enables automatic detection of the data rate on the first acquisition
following a Clear or configuration change.
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Item
Description
Manual
Allows you to manually specify the nominal data rate. This is useful when
the data pattern makes data rate detection ambiguous. As an example, a
“1 1 0 0 1 1 0 0” pattern at 8 Gb/s would otherwise be detected as a
“1 0 1 0” pattern at 4 Gb/s.
Bit Rate
In Manual configuration, allows you to specify the approximate data rate
in bits per second (b/s). In Auto configuration, displays the detected data
rate.
Off, On
Enables (On) or disables (Off) advanced clock recovery through a known
data pattern.
Pattern File Name
Browse
Selects a file to use for the data pattern.
OK
Accepts changes and closes.
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About PLL clock recovery setup. When PLL-based clock recovery is selected, the
application simulates the behavior of the hardware Phase Locked Loop clock
recovery circuit. This is a feedback loop in which the Voltage-Controlled
Oscillator (VCO) is used to track or follow slow variations in the bit rate of the
input waveform. Such loops are frequently used to recover the clock in
communication links that do not transmit the clock as a separate signal. The PLL
parameters in the application may be adjusted to simulate with the behavior of a
receiver in such a link, within certain guidelines.
NOTE. The effective transfer function of a PLL loop is not equal to the PLL Loop
BW setting. The Transfer function depends on the factors such as damping,
transition density and type.
NOTE. PLL response is not instantaneous. This causes some signals to have a
ramped trend at the beginning of a waveform as the PLL locks to the applied
signal. To avoid a PLL start-up transient, part of the output is blanked out. This
is applicable only when you select PLL Custom BW, PLL Standard BW or
Explicit Clock-PLL as the clock recovery method. PLL blanking is used by
measurements such as TIE, RJ, RJ-δδ, DJ, DJ-δδ, PJ, TJ@BER, High Voltage,
Low Voltage, High-Low, T n/t Ratio, Eye Width, Eye Height, Width@BER,
Height@BER, Rise Time and Fall Time.
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About PLL loop BW versus JTF BW. Phase locked loops are characterized
according to their bandwidth (BW), and several different bandwidths are
commonly used. The terminology used for these bandwidths is described here,
since it varies somewhat across different industries.
■
Loop BW (or Closed Loop BW) is the frequency at which the closed-loop
gain has fallen to -3 dB (half power) relative to unity-gain. The closed-loop
gain function has the character of a low-pass filter.
■
JTF BW (Jitter Transfer Function BW or Error Function BW) is the
frequency below which input jitter to a tracking loop is removed. The JTF
BW has a high-pass filter characteristic.
For Type I loops, the Loop BW and the JTF BW are always equal. For Type II
loops, these two bandwidths are different, and their ratio depends on the PLL
damping factor. You can choose to specify either bandwidth, and the other is
displayed for reference.
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PLL standard BW. The PLL control area provides control over the phase-locked
loop used for clock recovery. You can choose the loop bandwidth and the loop
order, and if a Type II loop is chosen, you can specify the damping factor.
To set the loop bandwidth automatically, based on a serial standard, select PLL:
Standard BW as the clock recovery method. From the Standard: b/s list box,
select the standard that matches your data link. For example, choose “PCI-E: 2.5”
to test a 2.5 Gbit/second PCI Express link. In this case, the PLL bandwidth will
be set to 1.5 MHz, which is 1/1667 of the baud rate as specified in PCI Express
standard.
You can use the PLL Model list box to choose between Type I and Type II loop.
A Type I loop has a transfer function that approaches zero frequency with a slope
of 1/s and a Type II loop approaches zero frequency with a 1/s2 slope (In much
of the PLL literature, these terms are used interchangeably with First-Order and
Second-Order loops. For a thorough discussion of loop type versus order, see
Frequency Synthesis by Phase Lock, by William Egan).
NOTE. Although it is possible to configure a Type II PLL with a bandwidth up to
1/10 of the baud rate, such a loop will have poor dynamic performance. This is
because Type II loops have less phase margin than Type I loops. A preferred
alternative to using a Type II PLL with a bandwidth close to its baud rate is to
use a second order high-pass measurement filter to emulate the effects of the
PLL.
Table 28: PLL-standard clock recovery options
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Item
Description
PLL Model
Selects between a Type I or Type II phase-locked loop.
Damping
Use the keypad to specify the damping ratio of the PLL. It is enabled only
for Type II phase-locked loop.
Loop BW
Displays the Closed Loop bandwidth that has been configured based on
the current standard.
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Item
Description
JTF BW
Displays the Jitter Transfer Function bandwidth that has been configured
based on the current standard.
Standard: b/s
Implicitly sets the loop bandwidth of the clock recovery PLL, based on
selection of the industry standard and data rate in bits/second.
Apply to All
Applies the current clock recovery configuration to all selected
measurements that have user-configurable clock recovery.
Apply
Applies the current clock recovery configuration to all selected
measurement(s) that have Clock Recovery as the configuration tab.
Advanced
Displays the Clock Recovery Advanced Setup. For more details, refer to
the Clock recovery advanced setup.
Related topics.
About PLL loop BW versus JTF BW
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PLL custom BW. The PLL control area provides control over the phase-locked
loop used for clock recovery. You can choose the loop bandwidth and the loop
order, and if a Type II loop is chosen, you can specify the damping factor.
To manually control the loop bandwidth, select PLL: Custom BW as the clock
recovery method and use the BW control to choose the –3 dB bandwidth, in Hz.
You can use the PLL Model list box to choose between a Type I and Type II
loop. A Type I loop has a transfer function that approaches zero frequency with a
slope of 1/s and a Type II loop approaches zero frequency with a 1/s2 slope. (In
much of the PLL literature, these terms are used interchangeably with First-Order
and Second-Order loops. For a thorough discussion of loop type versus order, see
Frequency Synthesis by Phase Lock, by William Egan).
If you choose a Type II loop, you can use the radio buttons to select whether you
will directly control the Loop BW (low-pass function) or the JTF BW (high-pass
function). You must also select the Damping Factor for a Type II loop.
NOTE. Although it is possible to configure a Type II PLL with a bandwidth up to
1/10 of the baud rate, such a loop will have poor dynamic performance. This is
because Type II loops have less phase margin than Type I loops. A preferred
alternative to using a Type II PLL with a high bandwidth is to use a 2 order highpass measurement filter to emulate the effects of the PLL.
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Table 29: PLL-Custom clock recovery options
Item
Description
PLL Model
Selects between Type I or Type II phase-locked loop.
Damping
Use the keypad to specify the damping ratio of the PLL. It is enabled only
for Type II phase-locked loop.
JTF BW
Explicitly sets the JTF bandwidth of the clock recovery PLL when the PLL
Model is Type II and the JTF BW radio button is selected.
Loop BW
Explicitly sets the Loop bandwidth of the clock recovery PLL when the
PLL Model is Type II and the Loop BW radio button is selected.
Apply to All
Applies the current clock recovery configuration to all selected
measurements that have user-configurable clock recovery.
Apply
Applies the current clock recovery configuration to all selected
measurement(s) that have Clock Recovery as the configuration tab.
Advanced
Displays the Clock Recovery Advanced Setup. For more details, refer to
the Clock recovery advanced setup.
Related Topics.
About PLL loop BW versus JTF BW
About explicit clock recovery. In Explicit Clock Recovery, the reference clock is
not derived from the measurement’s target source at all, but is instead taken from
a separately-identified source. Since the source used for the measurement now
differs from the source used to derive the reference clock, selecting this type of
clock recovery converts the measurement from a single-source measurement to a
dual-source measurement. The reference clock source is always shown on the
right when the two sources appear in a measurement table. Changing the clockrecovery method back to a non-explicit clock method will change the
measurement back to a single-source measurement.
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Explicit Clock-Edge. Select Explicit Clock-Edge method if you want to use the
edges found in the selected clock source (possibly multiplied up by an integral
number). If the Clock Multiplier is set to 1 (the default), only these edges will be
used. If the Clock Multiplier is set to a number N other than 1, linear
interpolation will be used between each pair of actual edges to create
N-1 additional reference edges. The interpolated edge times, combined with the
actual edges, give a total of N reference edge times per actual edge.
Table 30: Explicit-Clock edge options
Item
Description
Clock Source
Select Ch1 to Ch4, Ref1 to Ref4, or Math1 to Math4 as reference source
for clock recovery.
Clock Edge
Specify whether the rising, falling or both edges of selected source
should be considered.
Clock Multiplier
Specify the number of edges to be used.
Apply to All
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Apply
Applies the current clock recovery configuration to all selected
measurement(s) that have Clock Recovery as the configuration tab.
Advanced
Displays the Advanced explicit clock-edge dialog wherein you can adjust
the timing relation between reference clock source and data source.
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Advanced explicit Clock-Edge. To compare the reference clock times to the edge
times from the data source, some assumptions must be made about how they
align. The default assumption is that each data source edge is associated with the
reference clock edge to which it is nearest in time. This assumption may not be
optimum, for example if the probes for the reference clock and data signal have
different cable lengths.
To change the way the reference clock edges and data edges are associated, you
can control the Nominal clock Offset Relative to Data.
Table 31: Advanced explicit-Clock edge options
Item
Description
Auto
Automatically calculates the clock data skew and shifts the reference
clock edges before the application associates each data edge with the
closest clock edge.
Manual
Specify a time delay (positive or negative) to shift the reference clock
edge before the application associates each data edge with the closet
data edge.
Recalculate
When required
Recalculates the nominal clock offset value whenever a new
measurement is added or results are cleared or there are any
measurement configuration changes.
Every acquisition
Recalculates the nominal clock offset value for every acquisition.
Related topics.
Effect of nominal clock offset on eye diagrams
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Explicit Clock-PLL. Select Explicit Clock-PLL as the clock recovery method if
you want to feed the edges from the selected clock source through a PLL rather
than using them directly. The actual edges from the clock source will be used to
drive a software PLL model, and the edge times coming out of the PLL will be
used as the reference edges for the target measurement. If the Clock Multiplier is
set to a number N other than 1, the output of the PLL will have N edges per
actual edge.
Table 32: Explicit Clock-PLL options
Item
Description
Clock Source
Select Ch1 to Ch4, Ref1 to Ref4 or Math1 to Math4 as reference source
for clock recovery.
Clock Edge
Specify whether the rising, falling or both edges of selected source
should be considered.
Clock Multiplier
Specify the number of edges to be used.
Apply to All
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Apply
Applies the current clock recovery configuration to all selected
measurement(s) that have Clock Recovery as configuration tab.
Advanced
Displays the Advanced explicit clock-PLL dialog wherein you can adjust
the timing relation between reference clock source and data source.
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Advanced explicit Clock-PLL. In the Advanced Explicit Clock- PLL, you can
specify the PLL type, bandwidth, damping factor and nominal clock offset
relative to data. Damping numeric input is enabled only for Type II phase-locked
loop.
Nominal Clock Offset Relative to Data. To compare the reference clock times to the
edge times from the data source, some assumptions must be made about how they
align. The default assumption is that each data source edge is associated with the
reference clock edge to which it is nearest in time. This assumption may not be
optimum, for example if the probes for the reference clock and data signal have
different cable lengths.
To change the way the reference clock edges and data edges are associated, you
can control the Nominal clock Offset Relative to Data.
Table 33: Advanced Explicit-Clock PLL options
Item
Description
PLL Settings for Explicit Clock
JTF BW
Explicitly sets the JTF bandwidth of the clock recovery PLL when the PLL
Model is Type II and the JTF BW radio button is selected.
Loop BW
Explicitly sets the Loop bandwidth of the clock recovery PLL when the
PLL Model is Type II and the Loop BW radio button is selected.
PLL Model
Selects between Type I or Type II phase-locked loop.
Damping
Use the keypad to specify the damping ratio of the PLL. It is enabled only
for Type II phase-locked loop.
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Item
Description
Auto
Automatically calculates the clock data skew and shifts the reference
clock edges before the application associates each data edge with the
closest clock edge.
Manual
Specify a time delay (positive or negative) to shift the reference clock
edge before the application associates each data edge with the closet
data edge.
Recalculate
When required
Recalculates the nominal clock offset value whenever a new
measurement is added or results are cleared or there are any
measurement configuration changes.
Every acquisition
Calculates the nominal clock offset value for every acquisition.
Related topics.
Effect of nominal clock offset on eye diagrams
Effect of nominal clock offset on eye diagrams. Nominal Clock Offset does not
affect the eye diagrams directly. Data and clock timing relationship is maintained
ignoring the clock offset value. The clock offset still affects the eye diagram
shape indirectly through edge labeling and TIE measurement but not with
alignment.
When Explicit Clock Recovery is used, the Nominal Clock Offset does not affect
eye diagram alignment. The relative alignment between data and clock is
maintained as acquired. An absolute alignment is controlled by Ref Clock
Alignment setting in Eye Diagram plot configuration panel. To ensure proper
alignment between data and clock it is important to properly deskew oscilloscope
channels.
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Bit config
Bit config for eye height measurements. This configuration tab allows you to
select which waveform bit types (Transition bits, Non-Transition or All Bits) are
included when taking eye height.
Table 34: Bit config for eye height
Item
Description
Bit Type
All Bits
Eye analysis includes both transition and non-transition bits.
Transition
Eye analysis only on transition bits.
Non-Transition
Eye analysis only on non-transition bits.
Bit config for eye high eye low and Q-Factor measurements. This configuration tab
allows you to select which waveform bit types (Transition bits, Non-Transition or
All Bits) are included when taking eye height. This configuration tab also allows
you to set the percent of unit interval where the measurement is taken.
Table 35: Bit config for eye high, low, and Q-Factor
Item
Description
Bit Type
All Bits
Eye analysis includes both transition and non-transition bits.
Transition
Eye analysis only on transition bits.
Non-Transition
Eye analysis only on non-transition bits.
Measure at X% of the
Unit Interval
Sets the horizontal position where the measurement is taken, as a
percentage of the Unit Interval.
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Jitter, Noise and Eye-diagram analysis
Bit config for Height@BER measurements - Jitter Only. This configuration tab is
displayed for the Height@BER measurement when the analysis method selected
is Jitter Only (Preferences > Jitter Decomp > Analysis Method) .
Table 36: Bit config for Height@BER
Item
Description
Bit Type
All Bits
Eye analysis includes both transition and non-transition bits.
Transition
Eye analysis only on transition bits.
Non-Transition
Eye analysis only on non-transition bits.
Measurement Range (UI %)
70
Start
Start % value of UI
End
End % value of UI
# of Bins
The resolution by the number of bins into which Span is divided.
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Bit config for Height@BER measurements - Jitter + Noise. This configuration tab is
displayed for the Height@BER measurement when the analysis method selected
is Jitter + Noise (Preferences > Jitter Decomp > Analysis Method).
Table 37: Bit config for Height@BER
Item
Description
Signal Type
Clock
Clock Forces the signal to be interpreted as a Clock. Measurements will
take place on the edges specified by the Clock Edge control.
Data
Data Forces the signal to be interpreted as a Data. Both rising and falling
edges are used.
Auto
Allows the application to automatically detect whether the signal is clock
or data. If the signal is a clock, the Clock Edge control will determine
which edges are used; otherwise the Clock Edge control will have no
effect.
Vertical Position
Measure at X% of the
Unit Interval
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Sets the horizontal position where the measurement is taken, as a
percentage of the Unit Interval.
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Jitter, Noise and Eye-diagram analysis
Bit config for TN@BER measurement. This configuration tab is displayed for the
TN@BER measurement.
Table 38: Bit config for TN@BER
Item
Description
Signal Type
Clock
Clock Forces the signal to be interpreted as a Clock. Measurements will
take place on the edges specified by the Clock Edge control.
Data
Data Forces the signal to be interpreted as a Data. Both rising and falling
edges are used.
Auto
Allows the application to automatically detect whether the signal is clock
or data. If the signal is a clock, the Clock Edge control will determine
which edges are used; otherwise the Clock Edge control will have no
effect.
Vertical Position
Measure at X% of the
Unit Interval
72
Sets the horizontal position where the measurement is taken, as a
percentage of the Unit Interval.
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Bit config for mask hits measurements. This configuration tab allows you to select
the waveform bit type (All Bits, Transition, or Non-Transition) and the mask to
be used for Mask hits measurements.
Table 39: Bit config for mask hits
Item
Description
Bit Type
All Bits
Eye analysis includes both transition and non-transition bits.
Transition
Eye analysis only on transition bits.
Non-Transition
Eye analysis only on non-transition bits.
Mask
Browse
Allows selection of the mask file. (If none of the supplied mask files meets
your need, you may create a custom mask file with a text editor by using
one of the existing mask specification files as a template.)
Advanced
Advanced is only available for the AutoFit Mask Hits measurement.
Autofit determines the best mask offset. With Manual you select the mask
offset.
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Bit config for autofit mask hits measurement. This configuration tab allows you to
select the waveform bit type (All Bits, Transition, or Non-Transition) and the
mask to be used for Autofit Mask hits measurements and Advance options.
Bit config for mask
hits
Description
Bit Type
All Bits
Eye analysis includes both transition and non-transition bits.
Transition
Eye analysis only on transition bits.
Non-Transition
Eye analysis only on non-transition bits.
Mask
Browse
74
Allows selection of the mask file. (If none of the supplied mask files meets
your need, you may create a custom mask file with a text editor by using
one of the existing mask specification files as a template.)
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Bit config for mask
hits
Description
Advance
Displays the Mask Offset dialog box.
Autofit configuration: When Autofit is clicked, If “Autofit” configuration is
selected, the backend algorithm automatically identifies the best location
where the pixel hits are either minimum or zero in an eye diagram. The
“Horizontal Mask Offset” value will get updated in Autofit text box.
Manual configuration: If Manual configuration is selected, the positive
offset value will move the mask to the right side and negative offset value
will move the mask to left side of eye diagram. We should add a short line
of text at the bottom of the Horizontal section: “A positive value moves
the mask to the right”. There will be no mask movement for this particular
configuration (Manual = 0 seconds).
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Jitter, Noise and Eye-diagram analysis
Bit config for amplitude measurements. This configuration tab is present only for
High, Low and High–Low measurements. You can select the waveform bit type
(All Bits, Transition, Non-Transition) and method.
Table 40: Bit config for amplitude measurements
Item
Description
Bit Type
All Bits
Eye analysis includes both transition and non-transition bits.
Transition
Eye analysis only on transition bits.
Non-Transition
Eye analysis only on non-transition bits.
Measure the Center X Determines what percentage (1 to 100) of a unit interval, centered in the
% of the Bit
middle of the bit, shall be included in each measurement. The waveform
points selected by the percentage form a distribution (vertical histogram)
from which a single value is extracted, based on the Method control.
Method
76
Determines whether the Mean value or the Median of the selected
distribution is used for the measurement value for each unit interval.
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Bit config for PCI express measurements. This configuration tab allows you to
select which waveform bit types (Transition, Non-Transition or All Bits) are
included when taking PCI Express measurements, PCIe T-Tx-Rise and PCIe TTx-Fall.
Table 41: Bit config for PCI express measurements
Item
Description
Bit Type
BER for PCI express
measurements
All Bits
Analysis includes both transition and non-transition bits.
Transition
Analysis only on transition bits.
Non-Transition
Analysis only on non-transition bits.
The BER configure panel is available for T-TX-UTJ, T-TX-UDJDD, T-TXUPW-TJ,and T-TX-UPW-DJDD measurements.
Item
Description
Target BER
BER= 1E-?
Sets the Bit Error Rate exponent, thereby setting the statistical level at
which Total Jitter and Eye Opening are reported.
Apply To All
Apply
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Applies the Target BER value to both Jitter Target BER and Target BER
for all the measurements that have the BER as the configuration tab.
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RJ-DJ
About RJ-DJ. This configuration tab allows you to select an appropriate
decomposition method for jitter analysis. RJ-DJ decomposition analysis divides
the timing jitter into various categories and uses the results to predict the total
jitter at a selected bit error rate (BER).
The DPOJET application offers two methods of RJ-DJ analysis:
■
A method based on spectral analysis that is appropriate for cyclically
repeating data patterns.
■
A method that works for arbitrary data sequences.
This configuration tab allows you to guide the decomposition method based on
the data pattern. By default, the decomposition method is selected automatically
based on the detected bit pattern. This is the recommended configuration.
Table 42: RJ-DJ analysis of repeating options
Item
Description
Pattern Detection/
Control
Auto [Preferred]
Causes the data pattern to be detected automatically on the first
acquisition following a “Clear” or configuration change. Based on this
detection, the Pattern Type and associated controls are then configured
optimally for the given record length.
Manual
Allows (and requires) that the Pattern Type and associated controls be
set manually.
Pattern Type
Pattern Type Repeating
If the data signal is repeating pattern of N bits, then Repeating pattern
type should be selected. 1
Pattern Type - Arbitrary If the data signal is non-repeating pattern, or is unknown then Arbitrary
pattern type should be selected.
Pattern Length
1
78
(Present only when the Pattern Type is Repeating.) When Pattern
Detection is Auto, this field shows the detected pattern length. When
Pattern Detection is Manual, this control must be set to match the actual
pattern length. If the manually-set pattern length is inconsistent with the
detected pattern length, processing will continue but a warning will be
logged.
A minimum of 50 repeats of the pattern must be present.
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Item
Description
Window Length
(Only present when the Pattern Type is Arbitrary.) Determines the
number of unit intervals over which pattern correlation effects are
analyzed. The window should be set to a large enough value that the
impulse response of the serial data transmitter and channel have settled.
Target BER
BER= 1E-?
Sets the Bit Error Rate exponent, thereby setting the statistical level at
which Total Jitter, Total Noise and Eye Opening are reported.
NOTE. Target BER configuration is available only for TJ@BER,
Width@BER, Height@BER, BER mask test and PDF mask test
measurements.
Apply To All
Apply
Applies all settings on this configuration tab to all other measurements
that have an RJ-DJ tab.
Related topics.
RJ-DJ analysis of arbitrary pattern
RJ-DJ analysis of repeating patterns
RJ-DJ analysis of repeating patterns. This method of RJ-DJ analysis uses a
Fourier transform of the time-interval error signal to identify and separate jitter
components. It is described in the Fibre Channel - Methodologies for Jitter and
Signal Quality Specification (MJSQ) and has wide industry acceptance.
This method requires that the data signal be composed of a pattern of N bits that
are repeated over and over. A minimum of 50 repeats of the pattern must be
present. If you select Manual configuration, you must enter the pattern length
(N), although it is not necessary to know the specific bits that make up the
pattern. If you use the default “Auto” configuration, this method will be selected
if possible and configured based on the detected bit pattern.
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RJ-DJ analysis of arbitrary pattern. When the data pattern is not repeating, or is
unknown, a second method of RJ-DJ analysis may be used. (It may also be used
if the pattern is repeating, and correlates well with the Spectral method in this
case.) This method assumes that the Inter Symbol Interference (ISI) from a given
edge only affects a relatively small number of subsequent bits. For example, in a
band-limited link where a string of ones follows a string of zeros, the signal may
require three or four bit periods to fully settle to the “high” state.
In this method, an analysis window with a width of K+1 bits is slid along the
waveform. For each position of the window, the time interval error of the
rightmost bit in the window is stored, along with the K-bit pattern that preceded
it. After the window has been slid across all positions, it is possible to calculate
the component of the jitter that is correlated with each observed K-bit pattern, by
averaging together all the observed errors associated with that specific pattern.
In the configuration menu for the arbitrary-pattern method, the Window Length
field allows you to select how many bits are included in the sliding window. The
window should include enough bits to allow the impulse response of the system
under test to settle, usually 5 to 10 bits. The disadvantage of increasing the
window length is that it uses more memory and requires additional processing
time and greater measurement population to form an answer. If the measurement
population is not sufficient at the end of a processing cycle to calculate an
answer, the results table displays <Min# of UI.
Prior versions of DPOJET allowed direct control of the minimum number of
observations required for each data pattern, before a result would be produced.
This minimum is now set internally to 10. DPOJET always uses all available
observations; this control only set the minimum allowable.
The arbitrary pattern approach for measuring jitter may not be appropriate if there
are very-long-duration memory effects in your data link. An example would be if
there are impedance mismatch reflections that arrive long enough after the initial
edge to fall outside the analysis window.
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RN-DN
About RN-DN. This configuration tab allows you to select an appropriate
decomposition method for noise analysis. RN-DN decomposition analysis
divides the noise into various categories and uses the results to predict the total
jitter at a selected bit error rate (BER).
The DPOJET application offers two methods of RN-DN analysis:
■
A method based on spectral analysis that is appropriate for cyclically
repeating data patterns.
■
A method that works for arbitrary data sequences.
This configuration tab allows you to guide the decomposition method based on
the data pattern. By default, the decomposition method is selected automatically
based on the detected bit pattern. This is the recommended configuration.
Table 43: RN-DN analysis of repeating options
Item
Description
Pattern Detection/
Control
Auto [Preferred]
Causes the data pattern to be detected automatically on the first
acquisition following a “Clear” or configuration change. Based on this
detection, the Pattern Type and associated controls are then configured
optimally for the given record length.
Manual
Allows (and requires) that the Pattern Type and associated controls be
set manually.
Pattern Type
Pattern Type Repeating
If the data signal is repeating pattern of N bits, then Repeating pattern
type should be selected.
Pattern Type - Arbitrary If the data signal is non-repeating pattern, or is unknown then Arbitrary
pattern type should be selected.
Pattern Length
DPOJET Printable Application Help
(Present only when the Pattern Type is Repeating) When Pattern
Detection is Auto, this field shows the detected pattern length. When
Pattern Detection is Manual, this control must be set to match the actual
pattern length. If the manually-set pattern length is inconsistent with the
detected pattern length, processing will continue but a warning will be
logged.
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Item
Description
Window Length
(Only present when the Pattern Type is Arbitrary) Determines the number
of unit intervals over which pattern correlation effects are analyzed. The
window should be set to a large enough value that the impulse response
of the serial data transmitter and channel have settled.
Target BER
BER= 1E-?
Sets the Bit Error Rate exponent, thereby setting the statistical level at
which Total Jitter, Total Noise and Eye Opening are reported.
NOTE. Target BER configuration is available only for TN@BER
measurement.
Apply To All
Apply
Applies all settings on this configuration tab to all other measurements
that have an RN-DN tab.
Related topics.
RN-DN analysis of arbitrary pattern
RN-DN analysis of repeating patterns
RN-DN analysis for repeating pattern. This method of RN-DN analysis uses a
Fourier transform of the noise signal to identify and separate noise components.
This method requires that the data signal be composed of a pattern of N bits that
are repeated over and over. A minimum of 50 repeats of the pattern must be
present. If you select Manual configuration, you must enter the pattern length
(N), although it is not necessary to know the specific bits that make up the
pattern. If you use the default “Auto” configuration, this method will be selected
if possible and configured based on the detected bit pattern.
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RN-DN analysis for arbitrary pattern. When the data pattern is not repeating, or is
unknown, a second method of RN-DN analysis may be used. (It may also be used
if the pattern is repeating, and correlates well with the Spectral method in this
case.) This method assumes that the Inter Symbol Interference (ISI) from a given
edge only affects a relatively small number of subsequent bits. For example, in a
band-limited link where a string of ones follows a string of zeros, the signal may
require three or four bit periods to fully settle to the “high” state.
In this method, an analysis window with a width of K+1 bits is slid along the
waveform. For each position of the window, the time interval error of the
rightmost bit in the window is stored, along with the K-bit pattern that preceded
it. After the window has been slid across all positions, it is possible to calculate
the component of the jitter that is correlated with each observed K-bit pattern, by
averaging together all the observed errors associated with that specific pattern.
In the configuration menu for the arbitrary-pattern method, the Window Length
field allows you to select how many bits are included in the sliding window. The
window should include enough bits to allow the impulse response of the system
under test to settle, usually 5 to 10 bits. The disadvantage of increasing the
window length is that it uses more memory and requires additional processing
time and greater measurement population to form an answer. If the measurement
population is not sufficient at the end of a processing cycle to calculate an
answer, the results table displays <Min# of UI.
Prior versions of DPOJET allowed direct control of the minimum number of
observations required for each data pattern, before a result would be produced.
This minimum is now set internally to 10. DPOJET always uses all available
observations; this control only set the minimum allowable.
The arbitrary pattern approach for measuring jitter may not be appropriate if there
are very-long-duration memory effects in your data link. An example would be if
there are impedance mismatch reflections that arrive long enough after the initial
edge to fall outside the analysis window.
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Jitter, Noise and Eye-diagram analysis
Bus state
Configuring bus states. The following topic applies only to MSO series
oscilloscopes, since it depends on the ability to define a digital bus using the
oscilloscope logic channels.
Use this configuration tab to select the bus states, clock source, edge and polarity
used in measurements that require a bus source. The configuration changes based
on the selected measurement. Measurement tCMD-CMD requires two different
bus states to calculate the time between them. Select the bus states using a bus
symbol file or a bus pattern setup. Select between the options using the radio
buttons.
If a symbol file is not loaded, Enter pattern is selected. If a symbol file is loaded,
Use symbol file is selected. The symbol file loads commands into the drop down
lists. The Bus State user interface stays in sync with the Bus Setup window of the
oscilloscope. Any change in Bus state configuration tab will reflect in Bus setup
window and vice versa.
When a symbol file is loaded, the From Symbol and To Symbol drop downs are
displayed, with the commands loaded from the symbol file. You can select the
required Measure at bus states. Changing Measure at to Clock Edge lets you set
the clock source and polarity. Clock Edge considers the time at which commands
are registered, that is, at the Rising or Falling edge of the clock, depending on the
Clock Polarity configuration.
Measurements like tCKSRE require one waveform source and one bus state.
Select the waveform source from the Clock Source drop down or the Source
Configuration window. Your selected source is the first choice in the Clock
Source drop down. Select the bus state using the Symbol drop down.
The tBurst-CMD measurement is a single-source measurement by default. The
Measure at selection does not have a Clock Edge selection, only Start and Stop.
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Select Enter pattern to directly enter the required symbol bit patterns.
Table 44: Bus state options
Item
Description
Use symbol file
Use the bus state in the symbol file.
Enter pattern
Specify a bus state pattern.
Symbol File
Browse for the symbol file to use.
Symbol
The bus state symbol to use in measurements.
Measure at
Specify where to take the measurement.
Clock Edge Settings
Clock Source
Specify the clock source for the measurement.
Clock Polarity
Specify the clock polarity for the measurement.
Between bus states
From Symbol
Specify where the measurement is take from.
To Symbol
The symbol file specifies where to measurement to.
Measure at
The symbol file specifies where to take the measurement.
Start - Considers Start time of the command. Stop - Considers Stop time
of the command.Clock Edge - Considers the time at which Commands
are registered, that is, at the Rising edge of the clock.
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Edges
Configuring edges. This configuration tab allows you to select waveform edge(s)
the application should use to take measurement. Depending on the particular
measurement, the tab will offer access to other options and constraints that help
guide the analysis. The application is able to automatically detect whether a
signal is clock or data, and will do so by default. This can be overridden by
configuring the signal type as Clock or Data.
The configuration options for Edges change based on whether the analysis
method selected is Jitter Only or Jitter + Noise (Preferences > Jitter Decomp >
Analysis Method).
Configuring edges - Jitter only. The following configuration options apply to most
measurements when the analysis method selected is Jitter Only. See the
subsequent sections for Edge tabs corresponding to particular measurements.
Item
Description
Signal Type
Clock
Forces the signal type to be interpreted as a Clock. Measurements will
take place on the edges specified by the Clock Edge control.
Data
Forces the signal to be interpreted as a Data. Both rising and falling
edges are used.
Auto
Allows the application to automatically detect whether the signal is clock
or data. If the signal is a clock, the Clock Edge control will determine
which edges are used; otherwise the Clock Edge control will have no
effect.
Clock Edge
86
Rise
Uses only the rising edges of the signal.
Fall
Uses only the falling edges of the signal.
Both
Uses both the rising and falling edges of the signal.
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Configuring edges - Jitter + Noise. The following configuration options apply to
most Jitter measurements when the analysis method selected is Jitter + Noise.
The rise edge and fall edge configuration is disabled for Width@BER and all
Jitter measurements except TIE. For TIE measurement, the Clock Edge
configuration are enabled. See the subsequent sections for Edge tabs
corresponding to particular measurements.
Item
Description
Signal Type
Clock
Forces the signal type to be interpreted as a Clock. Measurements will
take place on the edges specified by the Clock Edge control.
Data
Forces the signal to be interpreted as a Data. Both rising and falling
edges are used.
Auto
Allows the application to automatically detect whether the signal is clock
or data. If the signal is a clock, the Clock Edge control will determine
which edges are used; otherwise the Clock Edge control will have no
effect.
Clock Edge
Rise
Disabled (greyed out)
Fall
Disabled (greyed out)
Both
Uses both the rising and falling edges of the signal (default).
The following configuration options apply to most Noise measurements when the
analysis method selected is Jitter + Noise. See the subsequent sections for Edge
tabs corresponding to particular measurements.
Item
Description
Signal Type
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Item
Description
Clock
Forces the signal type to be interpreted as a Clock. Measurements will
take place on the edges specified by the Clock Edge control.
Data
Forces the signal to be interpreted as a Data. Both rising and falling
edges are used.
Auto
Allows the application to automatically detect whether the signal is clock
or data. If the signal is a clock, the Clock Edge control will determine
which edges are used; otherwise the Clock Edge control will have no
effect.
Configuring edges for skew measurements. This configuration tab is displayed for
Skew measurements.
Item
Description
From Edge
Rise
Uses only the rising edges of the signal.
Fall
Uses only the falling edges of the signal.
Both
Uses both the rising and falling edges of the signal.
To Edge
88
Same as From
Each measurement is defined by a pair of like edges (Rise to Rise or Fall
to Fall).
Opposite as From
Each measurement is defined by a pair of opposing edges (Rise to Fall or
Fall to Rise).
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Configuring edges for differential CrossOver voltage measurements. This
configuration tab is displayed for Differential CrossOver Voltage measurements.
Item
Description
Rise
Uses only the rising edges of the signal.
Fall
Uses only the falling edges of the signal.
Both
Uses Both the rising and falling edges of the signal.
Configuring edges for phase noise measurements. This configuration tab is
displayed for Phase Noise measurements. Phase noise measurements are
undefined for data signals, so the signal is assumed to be a clock.
The Noise Integration Limits determine the portion of the phase noise spectrum
that is integrated to produce a single measurement per waveform acquisition.
Item
Description
Active Edge
Rise
Uses only the rising edges of the signal.
Fall
Uses only the falling edges of the signal.
Both
Uses both the rising and falling edges of the signal.
Noise Integration Limits
Upper Frequency
Sets the upper end of the noise integration frequency range.
Lower Frequency
Sets the lower end of the noise integration frequency range.
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Configuring edges for N-Period measurements. This configuration tab is displayed
for N–Period measurements.
Item
Description
Signal Type
Clock
Forces the signal to be interpreted as a Clock. Measurements will take
place on the edges specified by the Clock Edge control.
Data
Forces the signal to be interpreted as a Data. Both rising and falling
edges are used.
Auto
Allows the application to automatically detect whether the signal is clock
or data. If the signal is a clock, the Clock Edge control will determine
which edges are used; otherwise the Clock Edge control will have no
effect.
Clock Edge
90
Rise
Uses only the rising edges of the signal.
Fall
Uses only the falling edges of the signal.
Both
Uses both the rising and falling edges of the signal.
N=
Specifies number of cycles or unit interval in each N-period group.
Edge Increment
Specifies the temporal displacement in edges between consecutive
measurements.
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Configuring edges for setup/hold. This configuration tab is displayed for two
source measurements: Setup and Hold.
Item
Description
Clock Edge (Source1)
Rise
Uses only the rising edges of the signal.
Fall
Uses only the falling edges of the signal.
Both
Uses both the rising and falling edges of the signal.
Clock Edge (Source2)
Rise
Uses only the rising edges of the signal.
Fall
Uses only the falling edges of the signal.
Both
Uses both the rising and falling edges of the signal.
Configuring edges for CC-Period/Duty cycle measurements. This configuration tab
is displayed for the CC–Period, +Duty Cycle and –Duty Cycle measurements.
These measurements are only defined for clock signals, and each measurement
value is evaluated over one full clock cycle.
Item
Description
Clock Edge
Rise
Measurements are only initiated on the Rising edges of the clock signal.
Fall
Measurements are only initiated on the Falling edges of the clock signal.
Both
Measurements are initiated on both the Rising and falling edges of the
clock signal.
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Configuring edges for DCD measurement. This configuration tab is displayed for
DCD measurement.
Item
Description
Signal Type
Clock
Forces the signal type to Clock. Edges are selectable.
Data
Forces the signal type to Data. Both rising and falling edges are used.
Auto
Automatically detects whether the signal is clock or data.
Configuring edges for Overshoot/Undershoot measurements. This configuration is
displayed for both Overshoot and Undershoot measurements. The algorithm
calculates the maximum peak amplitude above/below the specified edge
configuration Reference level voltage for Overshoot/Undershoot measurements.
An Overshoot event is defined by a rising crossing followed by a falling crossing
of the reference level. Undershoot is defined by a falling crossing followed by a
rising crossing of the reference level.
The difference between the peak amplitude and the reference level voltage is
shown in the measurement results, expressed as a positive value in all cases. The
results are stored zero for the cycles which do not have Overshoot/Undershoot.
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Configuring edges for rise/fall slew rate.
This configuration is displayed for rise slew rate measurement:
Table 45: Configuration options for rise slew rate
Item
Description
From Level
Mid
Uses the source configuration mid reference voltage level for the Rise
slew rate.
Low
Uses the source configuration low reference voltage level for the Rise
slew rate. Default is low.
To Level
High
Uses the source configuration high reference voltage level for the Rise
slew rate. Default is high.
Mid
Uses the source configuration mid reference voltage level for the Rise
slew rate.
Slew Rate Technique
Nominal Method
Determines the slew rate between From -> Low level to To -> High level.
DDR Method
Determines the slew rate between low to high reference level. If the
actual signal is earlier than the nominal slew rate line, then the slew rate
is calculated using the tangent method From->Low level to To->High to
the sample, which occurred earlier.
This configuration is displayed for fall slew rate measurement:
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Table 46: Configuration options for fall slew rate
Item
Description
From Level
High
Uses the source configuration high reference voltage level for the Fall
slew rate. Default is high
Mid
Uses the source configuration mid reference voltage level for the Fall
slew rate.
To Level
Mid
Uses the source configuration mid reference voltage level for the Fall
slew rate.
Low
Uses the source configuration low reference voltage level for the Fall
slew rate. Default is low.
Slew Rate Technique
Nominal Method
Defines the slew rate between From -> Low level to To -> High level.
DDR Method
Determines the slew rate between high to low reference level. If the
actual signal is earlier than the nominal slew rate line, then the slew rate
is calculated using the tangent method From->High level to To->Low to
the sample, which occurred earlier.
Related topics
High mid and low reference voltage levels
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Configuring edges for time outside level. This configuration is displayed for the
Time Outside Level measurement:
Item
Description
Level
High
Time Outside Level measurement is computed only in overshoot using
High Ref Level.
High Ref Voltage
Displays or allows you to define the high reference voltage level.
Low
Time Outside Level measurement is computed only in undershoot using
Low Ref Level.
Low Ref Voltage
Displays or allows you to define the low reference voltage level.
Both
Time Outside Level measurement is computed in both overshoot and
undershoot using High and Low Ref Levels.
Related topics.
High mid and low reference voltage levels
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Configuring edges for F/N measurements - Jitter Only. This configuration tab is
displayed for F/N measurements.
Item
Description
Signal Type
Clock
Forces the signal to be interpreted as a Clock. Measurements will take
place on the edges specified by the Clock Edge control.
Data
Forces the signal to be interpreted as a Data. Both rising and falling
edges are used.
Auto
Allows the application to automatically detect whether the signal is clock
or data. If the signal is a clock, the Clock Edge control will determine
which edges are used; otherwise the Clock Edge control will have no
effect.
Clock Edge
Rise
Uses only the rising edges of the signal.
Fall
Uses only the falling edges of the signal.
Both
Uses both the rising and falling edges of the signal.
Subrate Divisor
N
96
Specifies the subrate divisor value 2 , 4, 8 which is used to compute F/2,
F/4, F/8 jitter measurement.
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Configuring edges for F/N measurements - Jitter + Noise. This configuration tab is
displayed for F/N measurements when the analysis method selected is Jitter +
Noise.
Item
Description
Signal Type
Clock
Forces the signal to be interpreted as a Clock. Measurements will take
place on the edges specified by the Clock Edge control.
Data
Forces the signal to be interpreted as a Data. Both rising and falling
edges are used.
Auto
Allows the application to automatically detect whether the signal is clock
or data. If the signal is a clock, the Clock Edge control will determine
which edges are used; otherwise the Clock Edge control will have no
effect.
Clock Edge
Rise
Disabled (greyed out)
Fall
Disabled (greyed out)
Both
Uses both the rising and falling edges of the signal.
Subrate Divisor
N
DPOJET Printable Application Help
Specifies the subrate divisor value 2 , 4, 8 which is used to compute F/2,
F/4, F/8 jitter measurement.
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Configuring edges for DDR tCH(avg) and DDR tCL(avg). This configuration tab is
displayed for both DDR tCH(avg) and DDR tCL(avg). Set the window size for
clock measurements. The measurement analysis is done on a sliding window of
size 200 cycles with a step increment of 1 cycle. You can set window size up to
1M, with at least 200.
Configuring edges for DDR tERR(m-n). This configuration tab is displayed for
DDR tERR(m-n) measurement.
Item
Description
Clock Edge
98
Rise
Measurements are only initiated on the Rising edges of the clock signal.
Fall
Measurements are only initiated on the Falling edges of the clock signal.
Minimum
Specify the minimum number of periods required to calculate error across
multiple consecutive cycles from tCK(avg).
Maximum
Specify the maximum number of periods required to calculate error
across multiple consecutive cycles from tCK(avg).
Window Size
Measurement analysis is done on a window of size 200 cycles with a step
increment of 1 cycle. As per the standard, the default window size is 200.
You can set window size up to 1M.
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Configuring edges for DDR tERR(n). This configuration tab is displayed for DDR
tERR(n) measurement.
Item
Description
Clock Edge
Rise
Measurements are initiated only on the Rising edges of the clock signal.
Fall
Measurements are initiated only on the Falling edges of the clock signal.
Number of Periods
Timing error (tERR) requires number of periods (n(per)) to calculate error
across multiple consecutive cycles from tCK(avg). You can configure
n(per) up to 50, with a resolution of 1.
Window Size
Measurement analysis is done on a window of size 200 cycles with a step
increment of 1 cycle. As per the standard, the default window size is 200.
You can set window size up to 1M.
Configuring edges for DDR tHZDQ and DDR tLZDQ. This configuration tab is
displayed for both DDR tHZDQ and DDR tLZDQ.
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Configuring edges for DDRtJIT(per) DDRtCK(avg) and DDRtJIT(duty). This
configuration tab is displayed for DDRtJIt(per), DDRtCK(avg) and
DDRtJIT(duty).
Item
Description
Clock Edge
SSC
Rise
Measurements are only initiated on the Rising edges of the clock signal.
Fall
Measurements are only initiated on the Falling edges of the clock signal.
Window Size
Measurement analysis is done on a window of size 200 cycles with a step
increment of 1 cycle. As per the standard, the default window size is 200.
You can set window size up to 1M.
Spread spectrum clocking (SSC). This configuration tab allows you to set the
nominal frequency of the Spread spectrum clocking (SSC).
Table 47: Spread spectrum clock
Item
Description
Nominal frequency
100
Auto
Allows the application to determine the frequency.
Manual
You enter the nominal frequency of the spread spectrum clock.
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General configuration (DPOJET)
One touch jitter
One Touch Jitter is a process for automatically performing complex jitter analysis
with a single menu selection. The process selects a waveform source, sets the
horizontal and vertical scales, chooses measurements, generates statistical results
and creates plot summary (Histogram, Spectrum, Bathtub and Eye Diagram). To
run this process, select Analyze > Jitter and Eye Analysis (DPOJET) > One
Touch Jitter.
By default, the DPOJET application chooses an appropriate source for the jitter
measurements from the available active source(s) (amplitude >50 mV) before
generating the jitter summary.
NOTE. If the source amplitude is not greater than 50 mV, the application displays
a message “Signal amplitude is extremely low for the selected source”.
The following logic is used if none or many sources are active:
■
None of the sources are active
■
Only one source is active
■
Two sources are active
■
Three sources are active
■
Four or more sources are active
Case 1: None of the sources are active. If none of the sources are active, you are
prompted to select any one of the Ch, Ref or Math sources. The selected source is
validated to have amplitude >50 mV. When the amplitude of the selected source
is >50 mV, then autoset is performed to increase vertical and horizontal
resolution of the signal. The selected source is assigned for all single source jitter
measurements. The results and plots are generated for a single sequence.
Case 2: Only one source is active. The application checks if the active source has
amplitude >50 mV. The selected source is assigned for all single jitter
measurements. The results and plots are generated for a single sequence.
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Case 3: Two sources are active. The application checks whether the active sources
are a differential pair. If so, it creates a Math waveform by taking the difference
of the two (Example: Math1=Ref1–Ref2). The lowest numbered Math waveform
is considered as the source for all single jitter measurements. The results and
plots are generated for a single sequence.
If the active sources are not a differential pair, the application checks if one of the
source is a clock with a period that divides the other sources. An explicit clock
recovery method derives the clock from the clock source. The application creates
explicit-clock measurements TIE, Height, TJ@BER, RJ–δδ, DJ–δδ and
Width@BER for the source. The results and plots are generated for a single
sequence.
If one of the active sources is not a clock, the application selects a single source
from the active sources using the following priority:
■
1st- Lowest numbered Math
■
2nd- Lowest numbered Channel
■
3rd- Lowest numbered Ref
The results and plots are generated for a single sequence.
Case 4: Three sources are active. The application checks whether one of the
active sources is a Math, which is defined as difference of two sources (Example:
Math1=Ref1–Ref2 ). The application selects the Math waveform as the source for
all single source jitter measurements. The results and plots are generated for a
single sequence.
If one of the active sources is not a Math, the application selects a single source
from the active sources using the following priority:
■
1st-Lowest numbered Math
■
2nd-Lowest numbered Channel
■
3rd-Lowest numbered Ref
The application creates single source jitter measurements. The results and plots
are generated for a single sequence.
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Case 5: Four or more sources are active. If four or more sources are active, the
application selects a single source from the active sources using the following
priority:
■
1st-Lowest numbered Math
■
2nd-Lowest numbered Channel
■
3rd-Lowest numbered Ref
The application creates single source jitter measurements for the selected source.
The results and plots are generated for a single sequence. The following figure
shows the summary plot after One Touch Jitter is performed.
Serial Data/Jitter guide
About serial Data/Jitter guide. The Serial Data/Jitter Guide allows you to set up,
configure and run a measurement without intimate knowledge about the control
menus.
Select Analyze > Jitter and Eye Analysis (DPOJET) > Serial Data/Jitter
Wizard to launch the Serial Data/ Jitter Wizard.
The Serial Data/ Jitter Wizard includes the following steps:
Select measurement
Configure measurement
Select source(s)
Configure autoset options
Select plots
NOTE. You can exit the Serial Data/Jitter Wizard without affecting any settings in
the DPOJET application by clicking anytime before clicking the button.
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Select measurement. In this step, you can select any of the listed measurements:
■
Period and Frequency
■
Skew
■
Time Interval Error (TIE)
■
Jitter Summary includes Total Jitter (TJ@BER), RJ, DJ, PJ, DDJ, TIE, and
DCD measurements and plots
■
Eye summary includes Height, Height@BER, Width, Width@BER, and Unit
Interval measurements and plots
By default, the Period and Frequency measurement is selected. Click Next to
accept the measurement and proceed to Configure Measurement. The transition
to next step is represented by
values.
on the left along with selections or default
About configuring measurement. By default, the configuration parameters are
displayed for Period and Frequency, TIE and Eye measurements. The Configure
Measurement option is available only for Skew and Jitter Summary. The
selection in the previous step is displayed on the left.
Configure skew measurement
Configure jitter summary measurement
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Configure measurement-Skew. If you select Skew in the previous step, you can
configure edges by selecting the From and To edges and set the measurement
limits.
Click Next to select the measurement sources.
Related topics.
Configure edges for skew measurement
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Configure measurement-Jitter summary. If you select Jitter Summary
measurement in the previous step, the bit rate and pattern length will
automatically be determined by DPOJET, thus the Configure Measurement
section is not required.
NOTE. The measurements that you select also determine the plot types.
Click Next to select the measurement sources.
Related topics.
RJ-DJ analysis parameters
RJ-DJ
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Select sources. In this step, you can select the measurement source(s). The source
selection depends on the measurement type. By default, Source1 is displayed
automatically for all the measurements depending on the waveform last used. If
Ch1/Ref1/Math1 is displayed for Source1, Source2 is Ch2/Ref2/Math2 else Ch1/
Math1/Ref1 will be selected as Source2.
The Source2 option is displayed only for two source measurements such as
Skew.
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Click Next to configure autoset.
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Configure autoset options. In this step, you can choose to automatically adjust the
oscilloscope settings or the reference levels before the measurement. The default
of Yes is recommended. By selecting No, you will retain the current oscilloscope
settings and/or ref levels.
Click Next to select plots.
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Select plots. In this step, you can select the plots that you want to display. The
measurements that you selected earlier also determine which plot types will be
available in this step. The following table lists the available plots for
measurements:
Table 48: Measurements and available plots
Measurement
Plots
Period and Frequency Period Trend, Period Spectrum, Period Histogram.
Skew
Skew Trend, Skew Spectrum.
TIE
TIE Trend, TIE Spectrum, TIE Histogram.
Jitter Summary
TIE Trend, TIE Spectrum, TIE Histogram, and Bathtub Curve.
Eye summary
Eye Diagram (Transition Bit), Eye Diagram (Non Transition Bit) Unit
Interval Histogram, and Eye Width@BER.
In this example, the selections shown are for a Period and Frequency
measurement.
Click Finish to start the acquisition sequence using the selected settings. The
Serial Data/Jitter Guide window closes and the results screen is displayed.
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NOTE. None of the user specified settings are retained if you click before
clicking .
Configuring for SSC (Spread Spectrum Clocking). Spread spectrum clocking
involves modulating the clock frequency of a device and high-speed serial signals
in a controlled manner. The purpose of using SSC modulation is to spread the
spectral energy to mitigate interference due to unintentional RF radiation. The
typical modulating frequency is 33.3 kHz.
The Serial Data wizard will configure DPOJET appropriately to see an open eye
diagram for a signal with SSC, by using PLL clock recovery to track the
modulation. If your goal is to analyze the SSC modulation profile versus time, a
different configuration is required. You can use the SSC-related measurements
(SSC Profile, SSC Mod Rate, SSC Freq Dev, etc) to configure DPOJET
appropriately for those purposes.
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Source configuration
Custom source name. Any oscilloscope source (Channel, Math, or Reference) can
have a custom label which is created or changed using the main oscilloscope
interface:
■
Channels: Vertical > Label
■
Maths: Math > Setup
■
References: File > Reference Waveform Controls
If a source has been assigned a custom label, both the native name and custom
name are shown on the Source Config panel. When sources with custom labels
appear in the measurement lists (for example, on the Select or Config panels of
DPOJET), only the custom label is shown. To see the native name, move the
mouse over the row in the measurement table; a tool tip displays the native name.
In these cases, the custom label is shown, followed by the native name in
parenthesis, for example DQS (Ch1).
The custom source names (DQ and DQS) appear in the following screens:
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■
Measurement table
■
Source configuration
■
Results
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■
Plots
■
Data snapshot
■
Data logging
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■
Measurement summary
■
Export results to Ref
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Sources setup. The application takes measurements from waveforms specified as
input sources. You can select an oscilloscope channel input (live), a reference or
a math waveform as the source and also view Labels of the selected waveforms.
Some measurements require a Bus as a source.
You can configure sources using any of the following options:
■
■
Click
icon in the table which lists the selected measurements.
Double-click anywhere on a row in the table that lists the selected
measurements.
The source selections depend on the selected measurement.
NOTE. Setup, Hold, V–DIff–Xovr, DC Common Mode and Skew are two source
measurements. The Source2 option is displayed only for two source
measurements.
When more than one single source measurement is selected, Apply to all single
source measurements option is enabled in the source configuration screen.
When more than one two source measurement is selected, Apply to all two
source measurements option is enabled in the source configuration screen.
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NOTE. Although any DPOJET measurement can be assigned a custom name
(Example: tDQSH), the custom name is not displayed in the DPOJET source
configuration screen. Instead, the default name for the corresponding
measurement is displayed.
Related topics.
Source autoset
Ref levels
Bus as a source
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Source autoset. The Source Autoset allows you to automatically adjust the
oscilloscope's vertical and/or horizontal settings for live sources (Ch1-Ch4) to
improve measurement accuracy.
The Vertical Scale option automatically checks the peak-to-peak level of live
sources. The vertical scale and offset of all signals with a peak-to-peak value less
than six divisions are adjusted so the peak-to-peak will be eight divisions. If the
maximum or minimum value of a signal is “clipped”, the vertical scale and offset
are adjusted so that the peak-to-peak value will be eight divisions.
The Horizontal Resolution option checks the Rise Time/Resolution and Fall
Time/Resolution of all live channels. The instrument horizontal resolution is set
to the largest value that does not cause the samples-per-edge of the fastest edge to
fall below five samples per edge. The option sets the acquisition sampling mode
to Real Time for signals with very high edge speeds. Horizontal Autoset, by
default, tries to set the record length corresponding to 10000 UI for any given
waveform at highest possible sample rate.
To automatically define both the vertical and horizontal settings for all channel
sources, select the Vert and Horiz button. The Vert and Horiz option also applies
an oscilloscope autoset on each channel before performing the vertical scale and
horizontal resolution autoset.
Follow these steps to automatically define the vertical or horizontal settings for
active sources:
1. Ensure that any channel waveform that you want to autoset is visible on the
oscilloscope.
2. Select one of the following options:
■ Vert & Horiz to autoset both vertical and horizontal setting.
■ Vert Scale button to autoset oscilloscope vertical settings only.
■ Horiz Res to autoset oscilloscope horizontal settings only.
3. Select Undo to return the oscilloscope to its state before autoset.
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Table 49: Autoset configuration options
Item
Description
Vertical Scale
If a channel waveform is clipped or does not exceed six vertical divisions,
adjust the scale so that the waveform occupies about eight divisions.
Horiz Res
Sets the horizontal resolution so that the number of samples on the
fastest transition (edge) exceeds a specified target.
Vert & Horiz
Performs a sequence: Oscilloscope Autoset, Vertical scale and
Horizontal resolution.
Undo
Returns to the settings present before an Autoset was performed;
disabled after measurements are taken until you perform another source
autoset.
Ref Levels Setup
Click Ref Levels Setup in the Source Configuration screen to hide/unhide
the Ref Levels Setup.
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Bus as a source. On MSO model oscilloscopes only, some measurements
(tCMD-CMD, GDDR5 tCKSRE, GDDR5 tCKSRX, and GDDR5 tBurst-CMD )
require a bus as a source. Set up the bus using the Bus Setup window of
TekScope, and set up the source using the Source Configurations window of
DPOJET. If you try to select a measurement that requires a bus, but no bus is
configured, a pop up asks you to set up a bus.
Clicking Bus Setup displays the Bus Setup window where you can configure a
bus.
You can select sources using the Source configuration window. The selected bus
is displayed and you can apply both the bus and analog source settings to all
similar measurements. If the measurement requires one bus source and one clock
source, the following Source Configuration window is displayed.
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If the measurement has only one bus source, and Source Autoset and Ref Level
Autoset are not required, then the following Source Configuration window is
displayed.
Related topic.
Sources setup
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Digital as a source. DPOJET supports the following measurement on Digital
channels. Digital source measurements are available only on
MSO5000/70000 series of instruments running with 64-bit Windows 7 OS.
Period/Frequency
measurements
Time measurements
Period
Skew
Positive Width
Setup
Negative Width
Hold
Frequency
+Duty Cycle
-Duty Cycle
CC-Period
+CC-Duty
-CC-Duty
Digital source selection. You can select any of the Digital channels (D0 – D15)
from the digital tab as shown below.
Left and Right arrows will display the previous and next set of digital channels as
shown below:
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Digital sources do not have Source Autoset available. Also, digital sources are
not used for performing Ref Level Autoset.
Configurations and features. All the configurations and the features that are
supported for analog sources are supported for digital sources as well.
Related topic.
Sources setup
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Ref levels. Timing measurements are based on state transition times. By
definition, edges occur when a waveform crosses specified reference voltage
levels. Reference voltage levels must be set so that the application can identify
state transitions on a waveform. By default, the application automatically chooses
reference voltage levels when necessary.
The DPOJET application uses three basic reference levels: High, Mid and Low.
In addition, a hysteresis value defines a voltage band that prevents a noisy
waveform from producing spurious edges. The reference levels and hysteresis are
independently set for each source waveform, and are specified separately for
rising versus falling transitions. There are two ways to set the reference voltage
levels: Automatic and Manual.
High, mid and low reference voltage levels. The application uses three reference
voltage levels: High, Mid, and Low:
124
■
For most measurements, the application only uses the Mid reference voltage
level. The Mid reference level defines when the waveform state transition
occurs at a given threshold.
■
For Rise Time and Fall Time measurements, the High and Low reference
voltage levels define when the waveform is fully high or fully low.
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Rising Versus Falling Thresholds. You can specify thresholds for each of the
reference voltage levels: High, Mid, and Low. The application uses the thresholds
to determine the following events:
■
A Low/Mid/High rising event, which occurs when the waveform passes
through the corresponding Rise threshold in the positive direction.
■
A Low/Mid/High falling event, which occurs when the waveform passes
through the corresponding Fall threshold in the negative direction.
For a given logical reference level (such as Low, Mid, or High), rising and falling
events alternate as time progresses.
NOTE. In many cases, the rising and falling thresholds for a given reference
voltage level are set to the same value. In those cases, a hysteresis value helps
prevent spurious edges produced by small amounts of noise in a waveform.
Using the hysteresis option. The hysteresis option can prevent small amounts of
noise in a waveform from producing multiple threshold crossings. You can use a
hysteresis when the rising and falling thresholds for a given reference voltage
level are set to the same value.
The reference voltage level ± the hysteresis value defines a voltage range that
must be fully crossed by the waveform for an edge event to occur. If the decision
threshold is crossed more than once before the waveform exits the hysteresis
band, the mean value of the first and last crossing are used as the edge event time.
For example, if the waveform rises through the Threshold – Hysteresis, then rises
through the Threshold, then falls through the Threshold, then rises through both
the Threshold and the Threshold + Hysteresis, a single edge event occurs at the
mean value of the two rising crossings.
Example of hysteresis on a noisy waveform.
Automatic versus manual reference voltage levels. Each measurement source can
be configured to automatically choose voltage reference levels (default), or to use
specific absolute reference voltages. In the automatic configuration, levels are
chosen according to percentages of the overall signal amplitude.
In the Ref Levels Setup panel, a table at the left edge contains all of the current
active measurement sources. If a source is configured for Percentages,
appropriate reference levels will be chosen, when necessary (typically when you
press the Single or Run button). Select Autoset at the right edge of the Source
Configuration menu to force autoset to occur and to learn which absolute voltage
will be used. For each level, the absolute voltage will be shown directly under the
corresponding control. If Autoset has not been selected recently, the values will
be shown as TBD; the last-used voltages will be displayed for reference.
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Normally, the reference levels used for rising and falling edges are identical for a
given threshold (High, Mid or Low). Some special cases demand different
thresholds for rising edges than for falling edges. In those cases, select the
Advanced check box to allow separate configuration based on polarity. The
Advanced view also allows you to adjust the Hysteresis value or choose the
Base-Top method.
For more details, refer to Understanding when ref level autoset will occur and
Understanding how ref level autoset chooses voltages.
Table 50: Configure sources ref levels autoset configuration
Item
Description
1
Calculates and displays the reference voltage levels for all sources where
the autoset option is set according to the Autoset Ref Level Setup.
Base top method
Specifies the Base-Top method to be used for all reference voltage levels
when autoset occurs.
Autoset
Understanding when ref level autoset will occur. When Autoset is enabled for a
given source, the individual reference levels are displayed but you may not
manually adjust them. Instead, the reference levels are automatically recalculated
whenever one of the following events occur:
■
A measurement sequence is initiated for the first time after a source has
become active.
■
A measurement sequence is initiated for the first time after all results have
been cleared.
■
The Autoset button at the right edge of the panel is pressed.
The Autoset button is provided as a convenience, but it is never required. Autoset
will always be run (if enabled) before an uninitialized source is used for a
measurement.
Understanding how ref level autoset chooses voltages. Once triggered, the
Reference Level Autoset function uses the following logic to determine actual
voltage levels.
For each applicable source, the Top (high logic level) and Base (low logic level)
are first determined. Then, the High, Mid and Low levels are calculated as
percentages of the Top-Base difference. For example, if the Top and Base are
2.8 volts and 0.4 volts respectively and the High percentage level is 90%, this
threshold would be calculated as:
HighThres= Base+ High Percent (Top-Base)= 0.4+0.9 (2.8–0.4)= 2.56
Manually adjusting the reference voltage levels. Whether or not you use the
application to automatically calculate the initial reference voltage levels, you may
1
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If you do not perform Autoset using the Autoset button, the application updates the reference levels (if required) when
you select Single or Run to take measurements.
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need to manually change the values. To set the reference levels manually, follow
these steps:
1.
Click
icon in the table which lists the selected measurements to view the
source configuration screen.
2. Select the desired source from the Source list.
NOTE. You cannot select inactive sources.
1. Select the Absolute button.
2. Select the reference levels or hysteresis options and manually adjust the
values. The values will not change when you select Autoset or take
measurements.
NOTE. A source will become inactive if all measurements on that source are
removed. If a new measurement is then added on that source, the source once
again becomes active, and defaults to Autoset. If you clear all measurement on a
source that was set to Manual, you must reselect the Manual state (if desired)
when the source is again added.
Click Percentage to set the reference levels in percentages.
Click Absolute to set the reference levels manually to specific voltages.
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Click Percentage to set the reference levels in percentages with advanced not
checked.
Click Absolute to set the reference levels manually to specific voltages with
advanced not checked.
Table 51: Configure sources ref levels configuration
Item
Calculates and displays the reference voltage levels for all sources where
the autoset option is set according to the Autoset Ref Level Setup.
Base top method
Specifies the Base-Top method to be used for all reference voltage levels
when autoset occurs.
Advanced
Allows you to set the Rise and Fall reference levels independently.
Absolute
Allows manually setting the reference levels.
Autoset
2
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Description
2
If you do not update ref levels by clicking Autoset, the application updates the reference levels (if required) when you
select the Single or Run to take measurements.
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Item
Description
Percentage
Allows setting the reference levels as a percentage.
20% – 80%
Sets the low threshold level to 20%, the mid threshold level to 50%, and
the high threshold level to 80%.
10% – 90%
Sets the low threshold level to 10%, the mid threshold level to 50%, and
the high threshold level to 90%.
Ref Levels Setup (one level per source)
3
3
Rise High
Sets the high threshold level for the rising edge of the source.
Rise Mid
Sets the middle threshold level for the rising edge of the source.
Rise Low
Sets the low threshold level for the rising edge of the source.
Fall High
Sets the high threshold level for the falling edge of the source.
Fall Mid
Sets the middle threshold level for the falling edge of the source.
Fall Low
Sets the low threshold level for the falling edge of the source.
Hysteresis
Sets the threshold margin to the reference level which the voltage must
cross to be recognized as changing; the margin is the relative reference
level plus or minus half the hysteresis; use to filter out spurious events.
Close
Accepts the changes and closes the window.
Default settings are 90% (High), 50% (Mid), 10% (Low), and 3% (Hysteresis).
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Base top method. Click Base top method in the Ref Level Setup screen to select
a method used for calculating Top and Base of the waveform.
When the reference levels are set to Autoset, which is the default, the following
steps are used during an autoset:
■
Base and Top of the waveform are calculated
■
High, Mid and Low reference voltages are determined as percentages of the
(Top - Base) difference
There are four methods to calculate the Base and Top of the waveform:
■
Min - Max
■
Low - High Histogram (Full Waveform)
■
Low - High Histogram (Center of Eye)
■
Auto
Table 52: Autoset ref level configuration
Item
Description
Min-Max
Uses the minimum and maximum values in the waveform to determine
the base and top amplitude. Useful on a waveform with low noise and
free from excessive overshoot.
Low-High Histogram
(Full Waveform)
Uses a histogram approach to determine the base top amplitude. Creates
a histogram of the amplitudes of the entire waveform; the histogram
should have a peak at the nominal high level, and another peak at the
nominal low level.
Low-High Histogram
(Center of Eye)
Uses a histogram approach to determine the base top amplitude. Creates
a histogram of the amplitudes in the center of each bit (unit interval) while
ignoring the waveform during bit transitions. The histogram should have a
peak at the nominal high level and another peak at the nominal low level.
Auto
Automatically determines the best Base Top method to use.
OK
Accepts the changes and closes the window.
Min - Max. The figure shows a typical data waveform with a vertical histogram
turned on. If base-top method Min-Max is selected, the voltages indicated by the
red lines is used for the base and top since these are the absolute min and max
points in the entire waveform. If there isn't too much overshoot in a waveform
this is a good base top method.
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Low - High Histogram (Full Waveform). If base-top method Low - High Histogram
(Full Waveform) is selected, the oscilloscope performs two histogram
measurements: one on the top half of the waveform and another on the lower half
of the waveform. The upper and lower blue lines in the figure show the modes of
the upper and lower histogram, respectively. The mode of a histogram is the
value that appears most frequently; visually, it is the peak of the histogram. It
does a good job of picking out the high and low logic levels to which the
waveform settles.
Low - High Histogram (Center of Eye). If base-top method Low - High Histogram
(Center of Eye) is selected, the waveform is assumed to be a serial data signal
and DPOJET performs clock recovery on the waveform. Then, the point at the
center of each unit interval is taken. These samples are sorted into low bits and
high bits. One histogram is formed on the low samples, and another on the high
samples. The Base and Top are the modes of these histograms. This is similar to
the Histogram Mode method Low - High Histogram (Full Waveform), except it
is less influenced by the shape of the waveform during transitions between bits.
Auto. Base-top method Auto is the default. In Auto, method Low - High
Histogram (Full Waveform) is tried first. But sometimes that method gives
ambiguous results because there's no clear point to choose on the histogram. If
that occurs, DPOJET switches to method Min-Max.
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Preferences setup
About preferences setup. The application provides Preferences Setup, where you
can set options that apply globally within DPOJET. These options remain
unchanged until you reset them. Click Analyze > Jitter and Eye Analysis
(DPOJET) > Preferences to view the Preferences screen. Optionally, click the
preferences shortcut that is available in the select panel of DPOJET and its
modules such as DDR, PCIE, and USB. To use the application more efficiently,
you can set the options in the following tabs:
Preferences-General
Preferences-Jitter decomp
Preferences-Measurement
Preferences-Path defaults
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Preferences-General. Click Analyze > Jitter and Eye Analysis (DPOJET) >
Preferences > General to view the following:
Table 53: Preferences-General options
Item
Description
View Log
Displays the error/warning log file in a Notepad window when the button
is pushed.
Clear Log
Clears the error/warning log file when the button is pushed.
Horizontal Display
Units
Select the horizontal display units for Time measurement results as
Seconds (default) or Unit Intervals. Unit Intervals are calculated for time
measurements which has Clock recovery only.
Vertical Display Units
Select the vertical display units for Noise measurement results as Volts
(default) or Unit Amplitude.
Default Image Type
Selects the default image format (JPEG, PNG or BMP) that will be used
by the functions that save images.
Notifier Duration
Determines how long the warning notifier will remain on the screen before
disappearing. (The notifier may also be dismissed manually).
Cancel
Discards all changes and closes the Preferences window.
OK
Accepts all changes and closes Preferences window.
Related topics.
Preferences-Measurement
Preferences-Path defaults
Preferences-Jitter Decomp
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Preferences-Measurement. Click Analyze > Jitter and Eye Analysis (DPOJET)
> Preferences > Measurement to view the following:
The Measurement tab allows you to limit Rise and Fall measurements to
transition bits only, or allow these measurements for all bits. Here, the transition
bits refer to edge transitions for which the preceding transition was only one unit
interval away. This may be important for signals with pre-emphasis, since the
transition following a string of two or more like bits has an intentionally low
swing that you may not want to measure.
Use this tab to enable or disable high-performance eye rendering. This provides a
trade-off between greater fidelity or greater rendering speed. You can also select
the waveform interpolation type.
Table 54: Preferences-Measurement options
134
Item
Description
Limit Rise/Fall
measurements to
transition bits only
When selected, determines whether Rise Time and Fall Time
measurements are performed on all bits or only on transition bits.
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Item
Description
Enable highperformance eye
rendering
Determines whether eye diagrams are optimized for speed or fidelity.
When disabled, all unit intervals (UI) in the waveform(s) are included in
the rendered eye. This gives the highest fidelity eye rendering, but can
take a considerable amount of time for long records. When this option is
enabled, a statistically representative subset of the UI is rendered, so that
eye diagrams for long waveforms can be displayed in a shorter time. The
rules for high-performance rendering are as follows:
■
If the waveform contains 15,000 or fewer UI, all the UIs in the
waveform are rendered.
■
If the waveform includes more than 15,000 UI, it is subdivided into
segments of 2000 UI each. The entire waveform is scanned to find
the specific UI, that are the worst-case violators for six different
points around the eye. For each of these worst case violators, the
entire segment of 2000 UI in which it lies is rendered. Depending on
whether multiple worst-case violators lie in the same segment or not,
as few as 2000 UI but typically from 8000 to 12,000 UI will be
rendered in the final eye.
UIs: Current number of UIs used to render eye diagram: Total number of
UIs in the current acquisition
Total: Total number of UIs used to render the eye diagram (when doing
multiple acquisitions): Total number of UIs in the total population (when
doing multiple acquisitions.
If high performance rendering is off: UIs X = UIs Y Population X =
Population Y
If high performance rendering is on: UIs X < UIs Y Population X <
Population Y
Halt free-run on a limit If any of the selected measurement fails a limit test in free run,
failure for any
sequencing is stopped.
measurement
Waveform Interpolation Select the type of interpolation that is used between sample points, to
Type
determine the exact time when a waveform crosses a reference voltage
level. Linear interpolation is faster but introduces distortion that raises the
jitter noise floor slightly. Sin(x)/x Interpolation, also known as Sinc
Interpolation, approaches theoretically perfect waveform reconstruction
but is computationally expensive.
NOTE. For Eye-High, Eye-Low, and Eye-Height measurements, Sin(x)/x
interpolation is always used for eye measurements independent of the
chosen interpolation type.
Cancel
Discards the changes and closes the window.
OK
Accepts the changes and closes the window.
Related topics.
Preferences-General
Preferences-Jitter Decomp
Preferences-Path defaults
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Preferences-Jitter decomp. Click Analyze > Jitter and Eye Analysis (DPOJET)
> Preferences > Jitter Decomp to view the following:
The Jitter Decomp tab allows you to select the Dual Dirac model and the Jitter
Separation model, and to select the minimum number of unit intervals required
for BUJ analysis.
Table 55: Preferences-Jitter Decomp options
136
Item
Description
Analysis Method
Select the analysis method as:
■
Jitter Only
■
Jitter + Noise
Dual Dirac Model
Determines which parameter-extraction method is used when RJ-DJ
separation is done under the Dual-Dirac model. This affects results for
the RJ–δδ and DJ–δδ measurements only. When Fibre Channel is
selected, RJ and DJ parameters are extracted according to guidelines
given in ANSI/INCITS Technical Report TR-35-2004 “Methodologies for
Jitter and Signal Quality Specification”. RJ and DJ values are selected
that cause an exact match between the bathtub curves from the dualdirac and the full analytical models at two prescribed BER levels. When
PCI/FB-DIMM is selected, RJ and DJ parameters are determined using
the methodology defined in the PCI Express Gen 2 and Fully-Buffered
DIMM specifications. In this technique, the bathtub curves are plotted on
a Q-scale that linearizes the tails of the bathtub, and the RJ and DJ
values are derived from where the asymptotes to the curves intersect the
BER=0 line.
Lock RJ Value
Selecting the Lock RJ Value calculates the measurements at the
specified random jitter value. The checkbox is unchecked by default.
Selecting the checkbox displays a text box where you can enter the RJ
value. The default value is 1ps.
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Item
Description
Jitter Separation Model Selects the type of jitter separation, Spectral Only or Spectral + BUJ.
Spectral Only identifies almost all categories of jitter, including Bounded
Uncorrelated Jitter (BUJ) that is periodic (PJ). However, it cannot
separate bounded random jitter from Gaussian random jitter. Spectral+
BUJ includes additional processing to identify bounded random jitter (also
called Non-Periodic Jitter or NPJ). NPJ is typically caused by crosstalk
from a signal on a different clock domain, and generally requires a higher
population of measurements for proper detection.
Minimum # of UI for
BUJ Analysis
Determines the number of unit intervals (UI) that must be processed
before jitter separation is performed. This item is only used for Spectral +
BUJ processing, and is not shown if the Jitter Separation Model is
Spectral Only. A higher number of UI will allow the separation algorithm
to detect lower levels of NPJ, but will typically require longer record
length, more acquisitions, or both. A lower number of UI will allow
processing to occur on smaller populations of UI, but may only identify
stronger forms of NPJ. Also, note that the number of UI processed for
BUJ analysis is only 17% to 33% of the total UI acquired in each
waveform.
Cancel
Discards the changes and closes the window.
OK
Accepts the changes and closes the window.
Related topics.
Preferences-General
Preferences-Measurement
Preferences-Path defaults
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Preferences-Path defaults. Click Analyze > Jitter and Eye Analysis (DPOJET)
> Preferences > Path Defaults to view the following:
The Path Defaults allows you to set the path for images, reports and log files.
Click Browse to modify the default directory path.
Table 56: Preferences-Path defaults options
Item
Description
Default image export
directory
Selects the directory to which images will be saved, unless overridden at
the time of the export.
Default logging export
directory
Selects the directory to which logs will be saved, unless overridden at the
time of the export.
Default report export
directory
Selects the directory to which reports will be saved, unless overridden at
the time of the export.
Cancel
Discards the changes and closes the window.
OK
Accepts the changes and closes the window.
Related topics.
Preferences-General
Preferences-Measurement
Preferences-Jitter Decomp
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Export data and
measurement
Export data snapshot-Statistics. You can save a snapshot of the current statistics
in .csv format. The default location is C:\%USERPROFILE%\Tektronix
\TekApplications\DPOJET\Logs\Statistics, where %USERPROFILE% represents
your user location.
Click Analyze > Jitter and Eye Analysis (DPOJET) > Export > Data
Snapshot > Statistics to view the following:
Table 57: Data snapshot- Statistics options
Item
Description
Select Target
Measurements
Displays the measurement list. Click a row to select the measurement. By
default, all measurements are selected.
Select All
Selects all the measurements in the list for saving statistics.
Clear All
Deselects all the measurements from the list.
Save Statistics
Save
Saves the current statistics of selected target measurements to a log file.
File Name
Browse
Allows you to choose the name and location where the .csv file will be
saved. The default name is YYMMDD_HHMMSS_Stats.csv. The default
directory is C:\%USERPROFILE%\Tektronix\TekApplications\DPOJET
\Logs, where %USERPROFILE% represents your user location.
Close
Accepts the changes and closes the window.
NOTE. The default location for saving log files can be changed in the Preferences
dialog box.
Related topics. Export data snapshot-Measurement
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Export data snapshot-Measurement. You can save a snapshot of the data points
in .csv format. The default location is C:\%USERPROFILE%\Tektronix
\TekApplications\DPOJET\Logs\Measurements, where %USERPROFILE%
represents your user location.
Click Analyze > Jitter and Eye Analysis (DPOJET) > Export > Data
Snapshot > Measurement to view the following:
Table 58: Data snapshot- Measurement options
Item
Description
Select Target
Measurements
Displays the measurement list. Click a row to select the measurement. By
default, all measurements are selected.
Select All
Selects all the measurements in the list for saving statistics.
Clear All
Deselects all the measurements from the list.
Save Measurements
Save
Saves the data points for current acquisition of selected target
measurements in a log file.
Folder
Browse
Allows you to choose the location where the .csv files will be saved. The
default directory is C:\%USERPROFILE%\Tektronix\TekApplications
\DPOJET\Logs\Measurements, where %USERPROFILE% represents
your user location.
File Names
View
140
Displays View log file names dialog box which lists the measurements
and their source(s) with corresponding log file name in
YYMMDD_HHMMSS_<Measurement Name>-<SourceName>.csv
format.
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Item
Description
Close
Accepts the changes and closes the window.
The View Log File Names dialog box lists the measurements and their source(s)
with corresponding log file name in YYMMDD_HHMMSS_<Measurement
Name>-<SourceName>.csv format. Click Close to close the dialog box. View
log file names
Related topics.
Export data snapshot
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Export measurement summary. Click Analyze > Jitter and Eye Analysis
(DPOJET) > Export > Measurement Summary to save the generated report in
C:\%USERPROFILE%\Tektronix\TekApplications\DPOJET\Reports, where
%USERPROFILE% represents your user location. The exported measurement
summary contains information only about application setup and configuration.
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Data logging
Data logging-Statistics. The application can continuously log (save to file) the
calculated statistics. You can save the statistics to a “comma separated value”
(.csv) file to import into a text editor, a spreadsheet, or an analysis tool.
By default, all measurements are selected. You can select individual
measurements by selecting the row in the table on the left.
The steps for logging statistics are:
1. Click Analyze > Jitter and Eye Analysis (DPOJET) > Data Logging >
Statistics to view the Logging Statistics screen.
2. Select the measurements that you want to log in the Select Target
Measurements table on the left. Click Select All to select all the
measurements for logging or click Clear All to deselect the current
measurements list.
3. Click On/Off to enable/disable automatic logging statistics for all selected
measurements.
4. Click Browse to select a directory.
The default directory is C:\%USERPROFILE%\Tektronix\TekApplications
\DPOJET\Logs\Statistics, where %USERPROFILE% represents your user
location.
Table 59: Log-Statistics options
Item
Description
Select Target
Measurements
Displays the measurement list. Select the check box to select the
measurement. By default, all measurements are selected.
Select All
Selects all the measurements in the list.
Clear All
Deselects all the measurements in the list.
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Item
Description
Off
Disables automatic logging for all selected measurements.
On
Enables automatic logging for all selected measurements.
Data Log File
Browse
Allows you to choose the name and location where the .csv file will be
saved. The default name is YYMMDD_HHMMSS_Stats.csv. The default
directory is C:\%USERPROFILE%\Tektronix\TekApplications\DPOJET
\Logs\Statistics, where %USERPROFILE% represents your user location.
NOTE. Microsoft Excel has a limitation where you cannot increase the number of
rows (65,536) or columns (256) beyond the maximum row and column limits.
Opening log files in or another analysis package is recommended. An error
message “File not loaded completely” is displayed, if you try to open a log file
with data exceeding the aforesaid row and column limits.
Related topics.
Data logging-Measurement
Data logging-Worst case
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Data Logging-Measurement. You can log the actual individual measurement data
values as measurement files.
1. Click Analyze > Jitter and Eye Analysis (DPOJET) > Data Logging >
Measurement to view the Logging screen.
2. Select the measurements that you want to log in the Select Target
Measurements table on the left. Click Select All to select all the
measurements for logging or click Clear All to deselect the current
measurements list.
3. Click On/Off to enable/disable logging for all selected measurements.
4. Click Browse to select a directory.
The default directory is C:\%USERPROFILE%\Tektronix\TekApplications
\DPOJET\Logs\Measurements, where %USERPROFILE% represents your
user location.
Table 60: Log-Measurements options
Item
Description
Select Target
Measurements
Displays the measurement list. Select the check box to select the
measurement. By default, all measurements are selected.
Select All
Selects all the measurements in the list.
Clear All
Deselects all the measurements from the list.
Log Measurements
Off
Disables automatic logging for all selected measurements.
On
Enables automatic logging for all selected measurements.
Folder
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Item
Description
Browse
Allows you to choose the name and location where the .csv file will be
saved. The default directory is C:\%USERPROFILE%\Tektronix
\TekApplications\DPOJET\Logs\Measurements, where %USERPROFILE
% represents your user location.
File Names
View
Displays View log file names dialog box which lists the selected
measurements with source(s) and their corresponding log file names in
<MeasurementName>_<SourceName>_YYMMDD_HHMMSS.csv
format.
View log file names. The View Log File Names dialog box lists the selected
measurements with source(s) and their corresponding log file names in
<MeasurementName>_<SourceName>_YYMMDD_HHMMSS.csv format. A
tool tip is displayed as shown on hovering the mouse over the text. Click Close to
close the dialog box.
The application displays a hint at the bottom of the screen under the following
conditions:
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■
Qualifier turned on for measurements in Global > Qualify with searches
specified.
■
Any sources other than search types are specified. Example Math instead of
Search1.
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Related topics.
Data logging-Statistics
Data logging-Worst case
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Data logging-Worst case.
1. Click Analyze > Jitter and Eye Analysis (DPOJET) > Data Logging >
Worst Case to view the Worst Case Logging screen.
2. Select the measurements which you want to log in the Select Target
Measurements table on the left. Click Select All to select all the
measurements for logging or click Clear All to deselect the current
measurements list.
3. Click On/Off to enable/disable worst case logging for all selected
measurements.
4. Click Browse to select a directory.
The default directory is C:\%USERPROFILE%\Tektronix\TekApplications
\DPOJET\Logs\Waveforms, where %USERPROFILE% represents your user
location.
Table 61: Log-Worst case options
Item
Description
Select Target
Measurements
Displays the measurement list. Select the check box to select the
measurement. By default, all measurements are selected.
Select All
Selects all the measurements in the list.
Clear All
Deselects all the measurements in the list.
Off
Disables the application to save worst case waveforms for all selected
measurements.
On
Enables the application to save worst case waveforms for all selected
measurements.
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Item
Description
Folder
Browse
Allows you to choose the name and location where the .csv file will be
saved. The default directory is C:\%USERPROFILE%\Tektronix
\TekApplications\DPOJET\Logs\Waveforms, where %USERPROFILE%
represents your user location.
File Names
View
Displays View log file names dialog box which lists the selected
measurements with source (labels) and their corresponding log file
names in <MeasurementName>_Min_<Source(label)>.wfm and
<MeasurementName>_Max_<Source(label)>.wfm 1 format.
View log file names. The View Log File Names dialog box lists the selected
measurements with source(s) and their corresponding log file names in
<MeasurementName>_Min_<Source(label)>.wfm and
<MeasurementName>_Max_<Source(label)>.wfm format. Click Close to close
the dialog box.
The application displays a hint at the bottom of the screen under the following
conditions:
1
150
For example, if the selected measurement is Skew1 with Ch1 and Ch2 as sources, then the file names will be
Skew1_Min_Ch1(DQS).wfm, Skew1_Min_Ch2(DQ).wfm, Skew1_Max_Ch1(DQS).wfm, and
Skew1_Max_Ch2(DQ).wfm.
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■
Qualifier turned on for measurements in Global > Qualify with searches
specified.
■
Any sources other than search types are specified. Example Math instead of
Search1.
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Logging worst case for mask hits measurement. The DPOJET application
supports worst case logging for the Mask Hits measurement. Whenever Mask
Hits is selected, there are two waveforms corresponding to maximum and
minimum values for each of the segment as shown in the following figure:
When an additional clock source (Clock Recovery > Explicit Clock Edge) is
included for the Mask Hits measurement, there are two waveforms corresponding
to maximum and minimum values for each of the source as shown:
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NOTE. All waveforms are displayed in the reports when worst case logging is
enabled. Worst case waveform logging is now supported for all search types. For
more details on the search types, refer to your oscilloscope online help.
Related topics.
Data logging-Statistics
Data logging-Measurement
Sequencing
Use the Control panel to start or stop the sequence of processes the application
and oscilloscope use to acquire information from a waveform. The application
then determines if the algorithm for the selected measurement can be applied to
the waveform information. Sequencing is the steps to acquire waveform
information, determine if the information is usable for the measurement, take the
measurement, and display the results (and plots if selected).
When you click Recalc, Single or Run, the corresponding button is changed to
Stop and the Progress indicator is displayed. For more details, refer to the
Control panel.
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The Progress Indicator displays the sequencer state. Select Stop, if you want to
interrupt the sequence before its completion.
For more details on progress bar status messages, refer to Progress bar status
messages.
Limits
A Limits file allows you to specify the Pass/Fail threshold for measurements.
Each DPOJET-based serial data application typically provides limits files that
include combinations of relevant measurements and statistical characteristics, and
an appropriate range of values for each combination.
The DPOJET application provides an example limits file, called
Example_Limits.xml, that is annotated to explain some of the methods of
assigning limits. You can create additional limits files by copying the example
and modifying it appropriately. You can specify limits for any of the result
parameters such as Mean, Std Dev, Max, Min, peak-to-peak, population,
MaxPosDelta or MinPosDelta. For each of these result parameters, you can
specify Upper Limit (UL), Lower Limit (LL), or Both. The measurement names
in the limits file must be entered as mentioned in
Setting up the application for analysis.
To include Pass/Fail status in the result statistics, you can create a limits file
using an XML editor or any other editor in the following format. If the file is
created in any other editor such as notepad, it should be saved in Unicode format.
<?xml version="1.0" encoding="utf-16" ?>
<Main>
<Measurement>
<NAME>Period</NAME>
<STATS>
<STATS_NAME>Mean</STATS_NAME>
<LIMIT>UL</LIMIT>
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<UL>1</UL>
<LL>0</LL>
<STATS>
<STATS_NAME>StdDev</STATS_NAME>
<LIMIT>LL</LIMIT>
<UL>1121</UL>
<LL>0121</LL>
</STATS>
<STATS>
<STATS_NAME>Max</STATS_NAME>
<LIMIT>BOTH</LIMIT>
<UL>1</UL>
<LL>0</LL>
</STATS>
<STATS>
<STATS_NAME>Min</STATS_NAME>
<LIMIT>UL</LIMIT>
<UL>0</UL>
<LL>1</LL>
</STATS>
<STATS>
<STATS_NAME>PeakToPeak</STATS_NAME>
<LIMIT>UL</LIMIT>
<UL>1</UL>
<LL>1</LL>
</STATS>
<STATS>
<STATS_NAME>MaxPosDelta</STATS_NAME>
<LIMIT>UL</LIMIT>
<UL>1121</UL>
<LL>1121</LL>
</STATS>
<STATS>
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<STATS_NAME>MinNegDelta</STATS_NAME>
<LIMIT>UL</LIMIT>
<UL>0</UL>
<LL>0</LL>
</STATS>
<STATS>
<STATS_NAME>Population</STATS_NAME>
<LIMIT>UL</LIMIT>
<UL>0</UL>
<LL>0</LL>
</STATS>
</Measurement>
</Main>
Table 62: Limits options
Item
Description
Pass/Fail Test
Off/On
Enables (On) or Disables (Off) the display of limit information in results.
Select On to choose a limits file for the selected measurement.
Limits File
156
Browse
To select an existing limits file or locate the directory.
Close
Accepts the changes and closes the window.
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Jitter, Noise and Eye-diagram analysis
Limits for mask hits. Limits are available for Mask Hits. The applications displays
the following in the results panel when limits are turned on (Analyze > Jitter and
Eye Analysis (DPOJET) > Limits):
If there is a hit in any of the segments, the result is FAIL as shown:
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Measurement summary
Measurement configuration summary-Measurement. Click Analyze > Jitter and
Eye Analysis (DPOJET) > Measurement Configuration Summary >
Measurement to view measurement, source and the configuration parameters of
each measurement.
Table 63: Measurement configuration information
Item
Description
Measurement
Displays the measurement name.
Source
Displays the selected source.
Others
Displays the other configuration information related to the selected
measurement.
OK
Closes the window.
Related topics.
Measurement summary-Ref levels
Measurement summary-Misc
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Measurement summary-Ref levels. Click Analyze > Jitter and Eye Analysis
(DPOJET) > Measurement Configuration Summary > Ref Levels to view the
ref level tab. This tab provides information about ref level configuration per
source. Displays the reference voltage levels for the high, mid, and low
thresholds for the rising edge and for the falling edge of each active source, and
the hysteresis.
Table 64: Ref level configuration information
Item
Description
Source
Displays the selected source.
Rise High
Displays the high threshold level for the rising edge of the source.
Rise Mid
Displays the middle threshold level for the rising edge of the source.
Rise Low
Displays the low threshold level for the rising edge of the source.
Hysteresis
Displays the threshold margin to the reference level which the voltage
must cross to be recognized as changing; the margin is the relative
reference level plus or minus the hysteresis; use to filter out spurious
events.
Fall High
Displays the high threshold level for the falling edge of the source.
Fall Mid
Displays the middle threshold level for the falling edge of the source.
Fall Low
Displays the low threshold level for the falling edge of the source.
OK
Closes the window.
Related topics.
Measurement configuration summary-Measurement
Measurement summary-Misc
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Measurement Summary-Misc. Click Analyze > Jitter and Eye Analysis
(DPOJET) > Measurement Configuration Summary > Misc tab to view
various configuration parameters. The Miscellaneous tab shows whether the
Gating, Qualify, and Stat Pop Limit functions are enabled; if enabled, it also
shows the source for qualification, the size for population, and various other
configuration choices.
Table 65: Miscellaneous configuration information
Item
Description
State
Displays On when Gating, Qualify and Population are enabled and Off
when they are disabled.
Source
Displays the selected source for qualify.
Size
Specifies the maximum population that can be obtained for each active
measurement.
OK
Closes the window.
Related topics.
Measurement configuration summary-Measurement
Measurement summary-Ref levels
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Results as statistics
Viewing statistical results
The application displays results for the measurements for all acquisitions or for
the current acquisition. By default in the detail view, the limits will not be shown
unless the limits are turned on.
Result statistics for most of the measurements show Population in terms of UI or
transitions. According to the JEDEC specification, the analysis for most of the
clock measurements is done for a 200-cycle moving window. However, for clock
measurements such as DDRtCL(avg) and DDRtCH(avg), the population is shown
as tCK(avg) units. For Data Eye Width, the population number is shown as per
acquisition.
Table 66: Results menu options
Item
Description
Displays an error message. You can click
information in a text editor.
Displays a warning. You can click
in a text editor.
to view the error log information
Description
Lists the measurement name and the source.
Mean
Lists a statistical mean value for the measurement data.
Std Dev
Lists a statistical standard deviation value for the measurement data.
Max
Lists a statistical maximum value for the measurement data. Shows Pass
if the statistics is within the specified Upper Limit Equality (ULE).
Min
Lists a statistical minimum value for the measurement data. Shows Fail if
the statistics has crossed the specified Lower Limit Equality (LLE).
p-p
Population
Max-cc
1
to view the error log
Lists a statistical peak-to-peak value for the measurement data.
1
Lists the total number of measurement data points used for displaying the
statistics.
Lists the maximum cycle-to-cycle differences per acquisition.
Jitter measurements such as RJ, DJ show population in terms of acquisitions.
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Item
Description
Min-cc
Lists the minimum cycle-to-cycle differences per acquisition.
Options
Click to view Save Current Stats, Export to Ref Waveform, and Display
Units-Absolute options.
Save Current Stats...
Saves the current statistics as log information.
Export to Ref
Waveform
Exports time trend data of the selected measurement to the reference
memory.
Display Units- Absolute Default display unit is Absolute.
Click to view the result details.
NOTE. For Mask Hits measurement, only Mean, Max, Min and Population values
are displayed in the results table. On clicking , Hits in Segment 1, Segment 2 and
Segment 3 are displayed. For Mask Hits measurements, mean indicates the total
number of hits for all acquisitions.
The results tab with limits turned on is as shown. You can click the zoom icon,
available for Max and Min values irrespective of the limits being turned on/off in
the current acquisition. A tool tip displays the message “Click to view the event
on the waveform” and appends the result statistics in full resolution (without any
truncation) on hovering the mouse.
NOTE. The zoom feature is available only for vector measurements.
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Results with Error/Warning Notification. The results tab with error
icon is as
shown. Click View Log to view the error log information in a text editor.
icon is as shown. You can click View Log to
The results tab with warning
view the error log information in a text editor.
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Overall Test Result. There are two ways to view the statistical results of
measurements:
■
Summary
■
Details
NOTE. Alternatively, you can toggle between Summary and Details using the
Expand/Collapse button.
On clicking Single/Run, the Overall Test Result shows Pass/Fail icons depending
on the result of the measurement(s).
For example, the Overall test result is fail if any measurement has limit failure.
The result statistic which has failed is highlighted in red as shown:
NOTE. When limits are turned off, Summary and Overall Test Result options are
not available.
Summary
Displays the summary of the results for all acquisitions. Pass/Fail information is
included whereas Max-cc and Min-cc information is excluded. Click the Expand
button for the summary view as shown:
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Details
Displays the detailed results specifying values for High Limit, Low Limit, High
Margin, Low Margin, Pass/Fail, and current acquisition. Click the Expand button
for the details view as shown:
Export results to ref
waveform
Using this option, you can export the time trend plot of a measurement to any of
the available reference memory, Ref1-Ref4. Click
on the right corner of the
results panel to select the “Export Results to Ref” option.
The Export Results to Ref waveform dialog box appears. It lists all the possible
measurements that have time trend result data (that is measurements for which
time trend plot is enabled in the plot panel).
From the list of measurements, results of any one measurement can be exported
to any one of the reference memory (Ref1-Ref4) which is not used as the source
of any measurement.
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Before exporting results to a reference memory, the application checks for the
following:
166
■
If any of the ref waveforms are already used as source for one of the
measurement(s), then you cannot export the results on those ref destinations.
The application prevents exporting by displaying an error message 2003.
■
If all the reference waveforms (Ref1-Ref4) are already used as sources for
various measurements, the “Export Results to Ref Waveform” is not
displayed. Instead, an error message 2002 is displayed.
■
If a ref destination is assigned to a measurement from the list which is not
empty (that is, if the ref is already defined and holds any other recalled
waveform), a warning prompts you from overwriting the existing definition
of the selected destination ref.
■
In case of any error (2002 or 2004) or warning (Overwriting the existing
definition) and you select the response as “No”, the destination ref reverts to
its previous value. For example, if the selected measurement is Period-Ref1,
and the destination ref assigned to the measurement is Ref3, and if you try to
change the destination from Ref3 to Ref1, an error message 2003 is
displayed. Ref3 is retained as the destination ref.
■
Time trend result export to the reference waveform for a measurement is
independent of time trend plot. Time trend result can be exported to ref
without selecting/defining plots in the plots panel.
■
If “Export Results to Ref” is selected without any measurement selection, an
error message 2005 is displayed.
■
If none of the selected measurements have time trend data, an error message
2007 is displayed and “Export Results to Ref” dialog is not displayed.
DPOJET Printable Application Help
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Bit rate and pattern length
detection
■
If the selected measurements have no results (results are cleared or
measurements are not run to produce results), an error message 2006 is
displayed and “Export Results to Ref” dialog box is not displayed.
■
If the destination is none for all measurements, the results are not exported to
ref on clicking OK. An information/warning 2008 is displayed.
Beginning with version 6.1.0, DPOJET performs automatic detection of bit rate
and pattern length whenever a new processing cycle occurs (for example, after a
configuration change or a “Clear” operation). The detected values are displayed
at the top of the results panel, to allow quick verification of overall test setup and
device configuration.
■
If there are simultaneous measurements on several different sources, the
results for the source associated with the first measurement will be shown
initially. The drop-down selector can be used to see the bit rate and pattern
length for other sources.
■
The reported bit rate can be influenced by the clock recovery settings, and in
particular by the Nominal Data Rate (if present) in the Advanced panel of the
clock recovery configuration tab.
■
If no repeating pattern is detected, or if jitter measurements are explicitly
configured to use arbitrary-pattern analysis, the second line will say Pattern:
Arbitrary.
■
By default, the detected pattern length also automatically configures any jitter
measurements that require pattern length as a configuration parameter. These
parameters appear on the RJ-DJ tab of the jitter measurements. If a jitter
measurement is configured to use a specific pattern length (instead of using
the detected length), the user-specified length will be shown at the top of the
results panel and will be used by the measurement even if it does not appear
to match the actual signal. To manually configure the pattern length, select
the configure tab and then the measurement. Select the RJ-DJ tab and select
the Manual button.
Related topics.
About RJ-DJ
Clock recovery advanced setup
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Result as plots
About plots
The application can display the results as two-dimensional plots for easier
analysis. Before or after you take measurements, you can set up the Select Plots
and Plots Configure menus to define up to four plots. The last plot selected is
displayed when the application completes Sequencing.
NOTE. Plots are not available for DDR tJIT(duty), DDR tJIT(per), DDR tERR(n),
DDR tERR(m–n), PCIe Tmin-Pulse, PCIe Med-Mx Jitter, PCIe Tmin-Pulse-Tj,
PCIe Tmin-Pulse-Dj, USB UI,DDR VID(ac), USB SSC FREQ DEV MAX and
USB SSC FREQ DEV MIN, ps21TXand T-TX-DDJ measurements.
If you set up plots after sequencing, the application displays the plot based on the
current measurement and result.
NOTE. When taking measurements in the Run mode, you must stop the sequencing
before you can use some plot features.
Table 67: Plot type definitions
Item
Description
Time Trend
Represents the measurement values versus the time location.
Data Array
Represents the measurement values versus the index number of the
measurement array.
Histogram
1
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1
Represents measurements sorted by value as a distribution of
measurement values versus the number of times the value occurred.
Spectrum
Represents the frequency content computed using the FFT of the Time
Trend of the measurement data.
Transfer
Represents the magnitude ratio of spectrum of time trend data of two
measurements from the following set: Clock Period, Clock Frequency,
Clock TIE, Clock PLL TIE, Data Period, Data Frequency, Data TIE, Data
PLL TIE.
Available for all measurements except Mask Hits, DDR tJIT(duty), DDR tJIT(per), DDR tERR(n), DDR tERR(m–n),
PCIe Tmin-Pulse, PCIe UI, and PCIe Med-Mx Jitter.
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Item
Description
Phase Noise
2
Represents the phase noise of a clock signal and is plotted in the
frequency domain for only Clock TIE measurements.
Eye Diagram
3
Represents data for the eye diagram based on the recovered clock as the
timing reference; used for mask testing.
Waveform
Bathtub
4
Represents the acquired waveform. It is available for use with eye
diagram mask tests to locate bit errors in the real-time waveform.
5
Q-Bathtub
Represents the Bit Error Rate versus the unit interval for measurements
that include RJ-DJ analysis.
6
Q-PulseWidth
Represents Q-Scale value versus the Unit interval for the
PCIe 3 Uncorrelated Jitter Measurements.
7
Represents Q-Scale value versus Time for the PCIe 3 Uncorrelated
Pulse Width Jitter Measurements.
Composite Jitter Hist
Noise Bathtub
8
BER Eye Contour
Plots four Histograms (TJ, RJ+BUJ, PJ, DDJDCD) together.
This plot shows the extrapolated curves due to noise like the way Bathtub
plot shows the extrapolated curve due to jitter.
9 10
This plot shows the Bit Error Rate contours at standard BER Levels like
1e-6, 1e-9, 1e-12, 1e-15, 1e-18 and Target BER on top of an
accumulated eye diagram.
Correlated Eye
This plot shows the data dependent eye with all uncorrelated effects
removed.
PDF Eye
This plot shows the underlying statistical model used to generate the
BER contours.
BER Eye
This plot shows the probability of a hit vs the location in the eye.
You can select the measurements from the displayed measurement list table on
the left. The Plots for the selected measurements are displayed in Select Plots.
The plots which are not applicable for the selected measurement are not available
under Select Plots. You can select up to 4 plots.
2
3
4
5
6
7
8
9
10
Available only for Phase Noise measurement.
Available only for all Eye, TIE and PCIe-T-TXA measurements.
Available only for Mask Hits measurement.
Available only for TJ@BER and Width@BER measurements.
Available only for PCIe TTX-UDJDD and PCIe TTX-UTJ measurements.
Available only for PCIe TTX-UPWTJ and PCIe TTX-UPWDJDD measurements.
Available only for TN@BER measurement.
Available only for Phase Noise measurement.
Available only for TN@BER measurement.
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Plot usage
This section provides a description of various plots of DPOJET.
Histogram plot usage
A Histogram plot displays the results such that the horizontal axis represents the
measurement values and the vertical axis represents the number of times that
each value occurred. Unlike most other plots, a histogram plot can accumulate
measurements over multiple acquisitions, up to a total population size of
2.1 billion.
Histograms are particularly useful in analyzing jitter. A histogram of the Time
Interval Error (TIE) represents the basis of jitter analysis using a histogram
approach. In a histogram, Deterministic Jitter (DJ) is bounded so that the
horizontal span of the plot will remain relatively constant. Random Jitter (RJ) is
unbounded and amplitude (horizontal span) will continue to grow as more
population is acquired. The TIE histogram provides a good way to quickly and
informally assess jitter.
Spectrum plot usage
A Spectrum plot is obtained from the Fourier Transform of measurement data
from a Time Trend. This plot is useful in identifying periodic frequency
components that contribute to timing errors, such as phase modulation.
When the signal has a repetitive data pattern, an analysis of the TIE Spectrum of
the signal can be used to separate Random Jitter (RJ) from Deterministic Jitter
(DJ) as well as to separate subcomponents such as Periodic Jitter (PJ), ISI and
DCD. Spectral components (spikes ) that do not correlate with the frequencies
contained in the data pattern can be a clue that external deterministic noise
sources are coupling into a system.
Data array plot usage
A Data Array plot shows measurement values versus measurement index, where
the indexes are always equally spaced along the horizontal axis. In contrast, the
measurement values on a Time Trend plot are not equally spaced along the
horizontal time axis.
Time trend plot usage
A Time Trend plot is a waveform trace of a measurement versus time. Each
measurement value is placed precisely at the time at which the measurement took
place. Measurements that involve two timing points are placed at the midpoint
between those two time. For example, a Risetime measurement is placed halfway
between the low threshold crossing and the high threshold crossing.
A Time Trend plot is useful, for example, in determining if the embedded clock
in a serial bit stream is modulated outside the capabilities of your receiver to
recover the clock. If the TIE time trend plot starts to take an unexpected periodic
shape, then this could indicate that you have uncorrelated periodic jitter from
crosstalk or from power supply coupling.
Bathtub plot usage
A Bathtub curve is the industry standard way of viewing the statistical Jitter Eye
Opening. A Bathtub curve represents eye opening as a function of the BER (Bit
Error Ratio). Most serial standards call for Total Jitter to be measured at a BER
of 10-12. The eye opening represented by the Bathtub Curve is what is left of the
unit interval after the total jitter measurement is subtracted.
The Jitter Eye opening and the Total Jitter have the following relationship:
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Total Jitter + Jitter Eye Opening = 1 Unit Interval
The Bathtub Curve plot shows the eye opening and total jitter values as functions
of the BER level. The plot is obtained from jitter analysis that performs RJ-DJ
separation.
Q-Bathtub plot usage
TTX-UTJ and TTX-UDJDD are two jitter measurements in the PCI Express
3.0 Compliance Specification. The Q-Bathtub plot provides a graphic
visualization of the Q-Scale extrapolation used to arrive at the measurement
value. The plot represents the Q-Factor value on the y-axis over one unit interval
on the x-axis and the extrapolation points are clearly indicated.
Q-PulseWidth plot usage
TTX-UPWTJ and TTX-UPWDJDD are two critical jitter measurements in the
PCI Express 3.0 Compliance Specification. The Q-PulseWidth plot provides a
graphic visualization of the Q-Scale extrapolation used to arrive at the
measurement value. The Q-Factor values lie on the y-axis, and the x-axis
represents a part of one unit interval significant for the measurement.
Phase noise plot usage
A Phase Noise plot shows a frequency domain view of the jitter noise on a
waveform normalized in an industry-standard way. The vertical axis is
logarithmic and uses the units of dBc/Hz, which means “decibels (relative to the
carrier) per Hertz”. The horizontal axis is logarithmic with units.
Transfer function plot usage
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A Transfer Function plot shows the magnitude ratio of the frequency spectrums
of two measurements on logarithmic axes. This can be a useful way to depict the
response of a system to stimuli at various frequencies, or to identify poles and
zeros in a system characteristic equation. Suppose that x(t) is a jitter
measurement at the input of a device, and y(t) is a corresponding jitter
measurement at the output of the device. The Transfer Function plot can be used
to show the following function, where X(f) is the Fourier Transform of x(t):
The horizontal axis of the Transfer Function plot goes up to the Nyquist
frequency of X or Y, whichever is lower. These plots work best if averaged
across multiple acquisitions to reduce the effects of measurement noise.
Waveform plot usage
The waveform plot is only applicable to the Mask Hits measurement. It depicts a
copy of the source waveform, with all mask violations denoted in a highlight
color. These are the same violations that appear on the Mask Hits eye diagram,
but the waveform plot allows them to be seen in the context of a continuous-time
waveform.
Eye diagram plot usage
An eye diagram is a plot of the voltage versus time for a serial bit stream, with
the time axis “wrapped” so that all unit intervals are superimposed on top of each
other in a time-aligned fashion. Because the resulting plot has many waveforms
overlaid, color grading is used to separate areas with many coincident waveforms
from areas that are only rarely crossed.
If there is an area free of waveforms in the center of the diagram, the eye is said
to be “open”, and a comparator circuit repetitively sampling the waveform at this
point in the unit interval could unambiguously separate the two logic states. For
experienced signal integrity engineers, the eye diagram allows many common
problems to be recognized instantly.
Composite jitter histogram plot usage
Composite Jitter Histogram plots 4 histograms (TJ, PJ, RJ+BUJ, DDJDCD)
together. This will be helpful in analyzing 4 components of jitter together.
Configurations for this plot are the same as that of Histogram Plot. This plot is
only applicable for Jitter measurements.
BER Eye contour plot usage
This plot shows the Bit Error Rate contours at standard BER Levels like 1e-6,
1e-9, 1e-12, 1e-15, 1e-18 and Target BER on top of an accumulated eye diagram.
Noise Bathtub plot usage
This plot shows the extrapolated curves due to noise like the way Bathtub plot
shows the extrapolated curve due to jitter.
Composite noise histogram plot usage
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Composite noise histogram plots 5 histograms (TN, PN, RN+NPN, DDN0,
DDN1) together. This will be helpful in analysing 5 components of noise
together.Configurations for this plot are the same as that of Histogram Plot. This
plot is only applicable for Noise measurements.
Correlated Eye plot usage
This plot shows the data dependent eye with all uncorrelated effects removed.
PDF Eye plot usage
This plot shows the underlying statistical model used to generate the BER
contours.
BER Eye plot usage
This plot shows the probability of a hit vs the location in the eye.
Selecting plots
Before or after you take measurements, you can set up plots for the selected
measurements by following these steps:
1. Click Plots in the Navigation panel to view the Select Plot window. The
currently active measurements and source(s) are displayed in the table on the
left (measurement table).
2. Click any of the plot icons that are available for the selected measurement.
The corresponding plot type and measurement are then added to a table on
the right (plot table).
3. Add another plot for the current measurement, or select a different
measurement and choose from its plot types. A maximum of four plots can
be selected at any given time.
Table 68: Plot selections
Item
Description
Plots
Lists only the plots which are available for the selected measurement.
Click a plot icon to add the plot type to the table on the right.
Clear Selected
Clears the selected plot from the plot table.
Clear All
Clears all plots from the plot table.
Configure
Allows you to adjust display options for the selected plot.
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Configuring plots
About configuring plots. Most plot types (except Data Array and Waveform) have
display options that can be adjusted for each instance of the selected plot.
The steps to configure a plot are:
1. Select a plot instance by clicking on a row from plot table on the right.
2. Click Configure to display a pop-up window with the available
configuration options.
3. Adjust the configuration options and click OK to accept the changes and
close the window.
4. Click Show Plots in the control panel to view the configured plot.
NOTE. The Show Plots icon appears in the only when one or more plots are
defined.
Related topics.
Configuring a time trend
Configuring a histogram plot
Configuring a spectrum plot
Configuring a transfer plot
Configuring a phase noise plot
Configuring an eye diagram for mask hits
Configuring an eye diagram plot for eye height
Configuring a bathtub plot
Configuring a composite jitter histogram plot
Configuring a composite noise histogram plot
Configuring a BER Eye contour plot
Configuring a BER Eye plot
Configuring a Correlated Eye plot
Configuring a PDF Eye plot
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Configuring a bathtub plot. Select a Bathtub plot in the table on the right and click
Configure to configure the plot.
Item
Description
Vertical Scale
Select the Vertical Scale as
1.
Log for logarithmic scaling of Vertical axis.(default)
2.
Linear for linear scaling of Vertical axis.
Minimum displayed
BER = 1E-?
Sets the lower axis for logarithmic plots to this value (expressed as the
negative of a base-10 exponent).
X-Axis Unit
Select the X-Axis Unit as Unit Interval or Seconds.
OK
Accepts the changes and closes the window.
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Configuring a spectrum plot. Select a Spectrum plot in the table on the right to and
click Configure to configure the plot.
176
Item
Description
Log
Selects logarithmic scaling for the vertical axis.
Linear
Selects linear scaling for the vertical axis.
Base
Sets the lower axis limit for logarithmic plots to this value (expressed as a
base-10 exponent). Available only when the vertical scale is log.
Log
Selects logarithmic scaling for the horizontal axis.
Linear
Selects linear scaling for the horizontal axis.
Mode
Selects whether the plot shows only the most recent spectrum, the
uniform average of all spectrums since the last time the results were
cleared, or the peak of the envelope of all spectrums since the last time
the results were cleared.
Normal - Shows magnitude values from the most recent acquisition.
Average - Averages the magnitude values at each frequency.
Peak Hold - Keeps the maximum value at each frequency.
OK
Accepts the changes and closes the window.
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Configuring a time trend. Select a Time Trend plot in the table on the right and
click Configure to configure the plot.
Item
Description
Vector
Connects measurement points with straight lines to form a continuous
waveform.
Bar
Places a vertical bar at the horizontal position of each measurement with
a height (positive or negative) that represents the value of that
measurement; a horizontal baseline represents the mean value of the
Time Trend.
OK
Accepts the changes and closes the window.
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Configuring a histogram plot. Select a Histogram plot in the table on the right and
click Configure to configure the plot.
Item
Description
Vertical Scale
Linear
Selects linear scaling for the vertical axis.
Log
Selects logarithmic scaling for the vertical axis.
Resolution
Defines resolution by the number of bins into which Span is divided: 25,
50, 100, 250, 500, 2000, and Maximum.
Horizontal Scale
178
Auto Scale
Causes the horizontal scale of the histogram to be adjusted automatically
based on the accumulated data points. If subsequently acquired data falls
outside the current horizontal scale, histogram bins are consolidated so
that the number of bins is preserved and the horizontal scale allows all
data to be plotted. When checked, disables the “Center” and “Span”
numerical inputs.
Center
Manually sets the value for the horizontal center of the Histogram, for
subsequent plot updates. You can set values up to 1 as (atto second)
using your keyboard.
Span
Manually sets the value for the total horizontal range of the Histogram, for
subsequent plot updates. You can set values up to 1 as (atto second)
using your keyboard.
Autoset
Uses the results of the latest acquisition to determine the logical values
for the Center and Span options (if the population of the measurement is
three or more).
OK
Accepts the changes and closes the window.
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Configuring a transfer plot. Select a Transfer Function plot in the table on the right
and click Configure to configure the plot.
Item
Description
Definition
Numerator
Measurement for which the magnitude spectrum is used as a reference.
Denominator
Measurement for which the magnitude spectrum is used to normalize the
numerator.
Vertical Scale
Linear
Selects linear scaling for the vertical axis.
Log
Selects logarithmic scaling for the vertical axis (default).
Horizontal Scale
Linear
Selects linear scaling for the vertical axis.
Log
Selects logarithmic scaling for the horizontal axis (default).
Mode
Selects whether the plot shows only the most recent spectrum, or the
uniform average of all spectrums since the last time the results were
cleared (default).
Normal - updates the plot with current values.
Average - averages the magnitude values at each frequency.
OK
Accepts the changes and closes the window.
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Configuring a phase noise plot. Select a Phase Noise plot in the table on the right
and click Configure to configure the plot.
Item
Description
Vertical Position
180
Baseline
Sets the lower axis limit for logarithmic plots to this value.
OK
Accepts the changes and closes the window.
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Jitter, Noise and Eye-diagram analysis
Configuring an eye diagram plot for eye height. Select an Eye Diagram plot (for all
eye measurements other than Mask Hits) in the table on the right and click
Configure to configure the plot.
Item
Description
Mask
On
Enables display and mask testing.
Off
Disables display and mask testing.
Browse
Select a mask file to import from the C:\Users\Public\Tektronix
\TekApplications\DPOJET\Masks directory.
Horizontal Scale
Auto Scale
When checked, causes the horizontal scale to be adjusted automatically.
Resolution
Manually sets the horizontal resolution, when Auto Scale is unchecked.
Superimpose
When checked, superimposes DQS eye onto the data eye diagram.
Reference Clock Eye (if
available)
Ref Clock Amplitude
Scale to Ref Clock
Scales the waveform to the one which is larger among the superimposed
eye when the Superimpose Reference Clock Eye option is checked.
Scale to Data
Autoscales to the vertical height of the data signal (DQ as in DDRA)
without regard to the reference clock (DQS) signal amplitude.
Ref Clock Alignment
Determines how an eye diagram is positioned on the plot. The position is
determined by the eye reference point, which is the location of
overlapping recovered or explicit clock edge locations. Typically, the eye
is located so that waveform edges are approximately at 25% and 75% of
the width of the diagram. This ensures that the eye opening is centered
on the plot facilitating cursor measurements and mask testing.
Auto
Determines the alignment property automatically. Eye diagram is aligned
automatically. Auto is typically equivalent to Left.
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Item
Description
Center
Eye reference point is centered on the plot. Center alignment is
appropriate for DDR Write bursts or other signals with explicit reference
clock where the clock and data signals are out of phase.
Left
Eye reference point is positioned on the left of the plot so that eye
opening is centered. Left alignment is appropriate for DDR Read bursts
and signals with recovered clock or explicit clock where the clock and
data signals are in phase.
OK
Accepts the changes and closes the window.
Related topics.
Effect of nominal clock offset on eye diagrams
NOTE. If there is unwanted skew between the data and explicit clock signals, the
channels must be properly deskewed. Refer to your oscilloscope online help on
how to deskew the channels.
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Configuring an eye diagram for mask hits. An eye diagram plot is activated
whenever a mask hits measurement is selected. Click Configure in the plots
panel to configure the plot.
Item
Description
Mask
Shows which mask has been selected (for the Mask Hits measurement,
the mask selection is performed as part of measurement configuration
rather than plot configuration).
Horizontal Scale
Auto Scale
When checked, causes the horizontal scale to be adjusted automatically.
Resolution
Manually sets the horizontal resolution, when Auto Scale is unchecked.
Superimpose
When checked, superimposes DQS eye onto the data eye diagram.
Reference Clock Eye
(if available)
Ref Clock Alignment Determines how an eye diagram is positioned on the plot. The position is
determined by the eye reference point, which is the location of
overlapping recovered or explicit clock edge locations. Typically, the eye
is located so that waveform edges are approximately at 25% and 75% of
the width of the diagram. This ensures that the eye opening is centered
on the plot facilitating cursor measurements and mask testing.
Auto
Determines the alignment property automatically. Eye diagram is aligned
automatically. Auto is typically equivalent to Left.
Center
Eye reference point is centered on the plot. Center alignment is
appropriate for DDR Write bursts or other signals with explicit reference
clock where the clock and data signals are out of phase.
Left
Eye reference point is positioned on the left of the plot so that eye
opening is centered. Left alignment is appropriate for DDR Read bursts
and signals with recovered clock or explicit clock where the clock and
data signals are in phase.
OK
Accepts the changes and closes the window.
Related topics.
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Effect of nominal clock offset on eye diagrams
NOTE. If there is unwanted skew between the data and explicit clock signals, the
channels must be properly deskewed. Refer to your oscilloscope online help on
how to deskew the channels.
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Configuring a composite jitter histogram plot. Select the Composite Jitter
Histogram (CJH) plot from the list on the right and click Configure to configure
the plot.
Table 69: Composite jitter histogram plot
Item
Description
Vertical Scale
Select the Vertical Scale as
1.
Log for logarithmic scaling of Vertical axis.
2.
Linear for linear scaling of Vertical axis (default).
Number of Bins
Resolution
Defines resolution by the number of bins into which Span is divided: 25,
50, 100, 250, 500, 2000, or Maximum.
Jitter Components
Selected checkbox values will be plotted
■
TJ
■
RJ+NPJ
■
PJ
■
DDJ+DCD
By default , all Jitter components will be checked.
OK
Accepts the changes and closes the window
NOTE. In CJH plot, the RJ+NPJ histogram values and RJ Trend are analytical
values when RJ is locked.
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Configuring a composite noise histogram plot. Select the Composite Noise
Histogram plot from the list on the right and click Configure to configure the
plot.
Table 70: Composite noise histogram plot
Item
Description
Horizontal Scale
Select the Horizontal Scale as
1.
Log for logarithmic scaling of horizontal axis.
2.
Linear for linear scaling of horizontal axis (default).
Number of Bins
Resolution
Defines resolution by the number of bins into which Span is divided: 25,
50, 100, 250, 500, 2000, or Maximum.
Noise Components
Selected checkbox values will be plotted
■
TN
■
RN+NPN
■
PN
■
DDN(0)
■
DDN(1)
By default , all Noise components will be checked.
OK
186
Accepts the changes and closes the window
DPOJET Printable Application Help
Jitter, Noise and Eye-diagram analysis
Configuring a noise bathtub plot. Select a Noise bathtub plot in the table on the
right and click Configure to configure the plot.
Item
Description
Horizontal Scale
Select the Horizontal Scale as
1.
Log for logarithmic scaling of horizontal axis (default).
2.
Linear for linear scaling of horizontal axis.
Minimum displayed
BER = 1E-?
Sets the lower axis for logarithmic plots to this value (expressed as the
negative of a base-10 exponent).
Y-Axis Unit
Select the Y-Axis Unit as Unit Amplitude or Volts.
Default - Unit Amplitude
OK
Accepts the changes and closes the window.
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Configure a BER Eye contour plot. Select a BER Eye contour plot from the list on
the right and click Configure to configure the plot.
Item
Description
Mask
On
Enables display and mask testing.
Off
Disables display and mask testing.
Browse
Select a mask file to import from the C:\Users\Public\Tektronix
\TekApplications\DPOJET\Masks directory.
Contour and Eye rendering
BER contours to
display
Enables the user to select or de-select BER contours of interest. By
default, all the standard BER contours are selected.
NOTE. Target BER determines the Target BER value which is configured
in RJDJ or RNDN for the measurements. The default Target BER value is
(1E-12).
OK
188
Accepts the changes and closes the window.
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Jitter, Noise and Eye-diagram analysis
Configure a BER Eye plot. Select a BER Eye plot from the list on the right and
click Configure to configure the plot.
Item
Description
Contour and Eye rendering
BER contours to
display
Enables the user to select or de-select BER contours of interest. By
default, all the standard BER contours are selected.
OK
Accepts the changes and closes the window.
Configure a Correlated Eye plot. Select a Correlated Eye plot from the list on the
right and click Configure to configure the plot.
Item
Description
Contour and Eye rendering
BER contours to
display
Enables the user to select or de-select BER contours of interest. By
default, all the standard BER contours are un-selected.
OK
Accepts the changes and closes the window.
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Configure a PDF Eye plot. Select a PDF Eye plot from the list on the right and
click Configure to configure the plot.
Item
Description
Contour and Eye rendering
Viewing plots
BER contours to
display
Enables the user to select or de-select BER contours of interest. By
default, all the standard BER contours are selected.
OK
Accepts the changes and closes the window.
About viewing plots. You can create and configure up to four plots. If you already
have measurement results, creating a plot will cause it to be displayed
immediately. If there are no current results, the plot will be created when you
sequence the application and results have been calculated. The Show Plots icon
appears in the control panel whenever at least one plot is defined. The Show Plots
icon appears in the control panel whenever at least one plot is defined. By
default, all defined plots windows are grouped in a single window on the upper
half of the display, but the window can be moved, resized, or dragged to a second
monitor. The application includes tools to help you select which plots to view, to
size and position the plot windows, to save plot information, to use the zoom
function, and to use the cursors functions.
If your Windows desktop is extended to a second monitor, you can drag the plots
window to the second monitor.
NOTE. When sequencing is complete, the plot window displays with the last plot
selected. The plot window also updates whenever you reconfigure a plot.
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Using a second monitor to view plots. If your oscilloscope setup includes a second
monitor that extends the Windows desktop, you can select and drag the title bar
of the plot window to position it in the second monitor. This allows you to
simultaneously display a waveform on the oscilloscope, measurement results, and
the plot for easy viewing.
Toolbar functions in plot windows. The Plot Toolbar window includes the
following functions:
Table 71: Plot toolbar functions
Icon
Functions
Export Figure.
Print Figure.
Zoom and Pan.
Vertical and Horizontal Cursor controls.
Moving and Resizing Plots.
Plot properties.
Plot Summary Views.
Full view of plots 1 to 4.
Moving and resizing plots. You can move and resize plot windows the same way
you would move and resize any window.
You can change the plot size to the whole display of the oscilloscope, or to half
the display. When viewing a plot in half the display, you can position the plot to
the top or bottom. The tools also return the plot to the original size. To position a
plot quickly on the oscilloscope, select one of the following tools in the plot
window:
■
■
enlarges the plot to fill the entire display.
positions the plot to the top.
■
positions the plot to the bottom.
■
always keep the plot on top layer.
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Using zoom in a plot. Once you have created a plot, you can use the Zoom tools to
examine the data at various scales.
TIP. If you prefer to use the zoom functions in a plot window with your finger, you
can activate the Touch Screen on the oscilloscope.
Table 72: Zoom functions in a plot
Item
Description
Zoom in (Horizontal and Vertical) – Expands part of the plot; the data
appears in more detail.
Zoom out – Contracts part of the plot; the data appears in less detail.
Zoom in (Horizontal only) – Expands the horizontal axis only and retains
the vertical axis.
Resets the zoom to 100%.
Changing the scale of data in a plot (Zoom). To change the scale of the data in a
Plot Details window, select one of the following plot zoom tools:
■
■
■
■
■
zooms in to expand the scale.
zooms out to contract the scale.
zooms in to expand the horizontal axis only.
moves the plot anywhere within the scale.
zooms in to restore the entire waveform data.
tool, you can use a select-drag-release action to expand
When you select the
part of the waveform (zoom in) by an arbitrary amount on both axes. After you
select (touch with a finger or click with the mouse) and begin dragging, a
bounding box shows what part of the waveform will be expanded upon release.
Select any part of the plot to expand the data by a factor of two (2X) equally on
both axes. Double selecting expands the data to the maximum factor.
To contract an expanded part of the data (zoom out), select anywhere on the data.
The view contracts to the values that existed before the most recent expansion of
the data. Selecting multiple times will restore successively earlier views. To
expand the scale of the horizontal axis only by a factor of two (2X), click a part
of the waveform. The plot retains the scale of the vertical axis.
TIP. Select
192
to see the entire available waveform.
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Jitter, Noise and Eye-diagram analysis
Using cursors in a plot. Cursors allow you to view numerical values associated
with a plot based on cursor locations. There are two types of cursors:
■
Horizontal cursors
■
Vertical cursors
Table 73: Cursor functions in a plot
Item
Description
Displays the vertical coordinate where each cursor touches the plot and
the difference (Δ) between the cursors.
Displays the horizontal coordinate where each cursor touches the plot
and the difference (Δ) between the cursors.
Brings the cursors into the visible part of the plot.
Displays the plot properties.
Cursors in a plot. You can use cursors to read the coordinate where each cursor
(line) touches the plot and also view the difference (Δ) between the two cursors.
The steps to use cursors in a plot details window are:
1. Select any of the following cursors:
■
■
■
to use horizontal cursors.
to use vertical cursors.
to bring cursors into the visible plot.
2. Select and drag either cursor to move the cursor to the desired part of the
plot. The cursor readout changes to reflect the cursor position.
NOTE. You can drag cursors only when the Zoom functions are disabled.
TIP. If you prefer to move the cursors in the plot window with your finger, you
can activate the touch screen on the oscilloscope.
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Exporting plot files. You can export plot image in Plot Toolbar window. Click
to save the contents of the plot window in any of the format as a MATLAB
figure format (.fig), .bmp, .jpg, .png, .emf, .tif, .mat and .csv.
The steps to export a plot file are:
1. Set up the plot window.
2.
Select
to save the plot as a figure.
3. Select the directory and enter a file name.
4. Click Save. The application saves the file in C:\%USERPROFILE%
\Tektronix\TekApplications\DPOJET\images, where %USERPROFILE%
represents your user location.
Printing plots. The steps to print a plot are:
1. Verify that the printer is configured.
2. Set up the plot window with zoom, cursors, or grid functions.
3. Click
icon in the plot details/summary window. The Print Preview
dialog is displayed.
4. Click
to set up the printing options and print a plot file.
NOTE. You can customize the print layout using the MATLAB page setup options.
The DPOJET online help does not provide information on MATLAB page setup.
For more information, refer to the MATLAB documentation.
Reports
About reports
194
You can use the Reports to configure and generate a compliance report to view
later or to share with others. You can also access reports using Analyze > Jitter
and Eye Analysis (DPOJET) > Reports. You can select the option which you
want to display in the report as shown in the following table:
DPOJET Printable Application Help
Jitter, Noise and Eye-diagram analysis
NOTE. When only the Mask Hits measurement is selected, the report shows only
the Pass/Fail information. If any other measurement having limits is selected
along with the Mask Hits measurement, limit information section is also included
in the generated report.
Table 74: Report generation options
Item
Description
Auto increment report
name if duplicate
Select/Clear the option to auto increment the report name if its already
existed. The auto generated report is of
YYMMDD_HHMMSS_savedfile.mht format.
Display units in
separate column
Select this option to display units in separate column
View report after
generating
Select this option to view the report after generation.
Report Name
Lists the directory path where the last generated report is stored.
Save
Saves the changes in the default report directory. Manipulates the report
name based on “Auto increment report name if duplicate” option.
Save As
Displays the browser where you specify the directory to save the
generated report. You can also edit the report name in the Save As
browser. By default, the generated report is saved in C:\
%USERPROFILE%\Tektronix\TekApplications\DPOJET\Reports, where
%USERPROFILE% represents your user location.
Append
Adds the current settings to an existing report.
View
Opens the generated report in the default browser.
Include pass/fail results Select/Clear the option to include/exclude the pass/fail status in the
summary
generated report.
Included detailed
results
Select/Clear the option to include/exclude the measurement result details
in the generated report.
Include plot images
Select/Clear the option to include/exclude the plot images like
measurement plots and oscilloscope waveform in the generated report.
Saving a report from Internet Explorer does not save plot images.
Include setup
configuration
Select/Clear the option to include/exclude the setup information like
DPOJET version, oscilloscope version, and status in the generated
report.
Include complete
application
configuration
Select/Clear the option to include/exclude the complete configuration
details in the generated report.
Save waveform file(s)
along with report
Select/Clear the option to include/exclude the oscilloscope waveform
details in the generated report.
Include user comments Select the option to include any comments in the generated report. To do
so, click the Add/Edit comments button.
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Reports Format. The generated reports are in .mht format and includes the
following configured set of information:
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■
Comments displays any user comments.
■
Setup Configuration such as DPOJET version and oscilloscope version.
■
Measurement Configuration such as measurement name, source and other
configuration parameters. Click on the measurement name to view the
oscilloscope waveform details.
■
Source Reference Levels displays the reference voltage levels for the high,
mid, and low thresholds for the rising edge and for the falling edge of all
sources, and the hysteresis.
■
Miscellaneous Settings such as Gating, Qualify and Population status.
■
Pass/Fail Summary indicating the Pass/Fail status for the selected
measurements. Also displays the limits information for measurements
selected along with Mask Hits.
■
Measurement Results with statistics.
■
Plot Images includes both selected plots and oscilloscope waveforms.
■
Reference waveforms stored at includes the location of the waveforms used.
DPOJET Printable Application Help
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Append Reports. Click the Append button to add the generated report to an
existing report of the same format. The application prompts you with a message
“Do you wish to append the current results to xxx.mht”? before the append
action.
NOTE. Time stamp differentiates various appended reports.
Reports compatibility. The application displays a warning when you try to
append the report with other reports, generated using previous versions of
DPOJET. Click Yes to overwrite an old report with a newer format.
NOTE. If there is not enough disk space to save the report, the application
displays “Cannot save file: There may not be enough free disk space. Delete one
or more files to free disk space, and then try again”.
Printing reports. You need to set the following while printing reports to get the
alternate gray and white rows in the table:
■
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Select Internet Explorer, go to Tools > Internet Options.
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■
In the Advanced tab, select the option Print Background Color and Images
under Printing as shown.
Saving waveform files. You can save waveform(s) used for the measurement by
checking the option “Save Waveform file(s) along with report” in the reports
screen. The waveforms are stored under C:\%USERPROFILE%\Tektronix
\TekApplications\DPOJET\Reports, where %USERPROFILE% represents your
user location.
If one or more waveforms are to be saved, the report name is incremented for
every append action by including a number in the parenthesis as shown:
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NOTE. If the waveform path name is greater than 128 characters, the
applications displays a warning even though the waveform is created with a
truncated name (without a .wfm extension).
Add Comments. Check “Include user comments” option to include the comments
in the generated report. Click Add comments in the report panel to include
comments in the report. Add Comments changes to Edit Comments in the
report panel until all the contents are cleared in the Comment dialog box.
Item
Description
Clear
Clears the edited contents.
Copy
Copies the edited contents.
Paste
Pastes the copied contents in the new comments dialog box even after
closing the window without clicking “Ok”.
Cancel
Closes the dialog box without saving any added contents.
OK
Saves the edited text.
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Tutorial
Introduction to the tutorial
This tutorial teaches how to set up the application, take measurements, and view
results as plots or statistics.
Before you begin the tutorial, perform the following tasks:
■
Set up the oscilloscope.
■
Start the application.
■
Recall the tutorial waveform.
NOTE. The screen captures shown in this section are from a DPO7254
oscilloscope.
Setting up the oscilloscope
The steps to set up the oscilloscope are:
1. Click File > Recall Default Setup in the oscilloscope menu bar to recall the
default settings.
2. Press the individual CH1, CH2, CH3, and CH4 buttons as needed to add or
remove active waveforms from the display.
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Tutorial
Starting the application
Click Analyze > Jitter and Eye Analysis (DPOJET) > Select to open the
application.
Waveform files
The application provides the following tutorial waveforms:
■
Rt-EyeTutorial.wfm
■
ckminus_50gs_18g_20m_pat1.wfm
■
ckplus_50gs_18g_20m_pat1.wfm
■
dplus_50gs_18g_20m_pat1.wfm
■
dminus_50gs_18g_20m_pat1.wfm
The waveform files are found at C:\Users\Public\Tektronix\TekApplications
\DPOJET\Examples.
Recalling a waveform file
To recall a waveform file, follow these steps:
1. Click File > Recall in the oscilloscope menu bar to display the Recall dialog
box.
NOTE. If the application is in button mode, select the Recall button to recall
the tutorial waveform.
2. Click Waveform icon in the left of the Recall dialog box.
3. Select Ref1, Ref2, Ref3, or Ref4 as the Destination option.
4. Browse to select the waveform. Use the keypad to edit the waveform file
name.
5. Click Recall. The oscilloscope recalls and activates the Reference Waveform
control window.
6. Click On to display the waveform.
7.
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Click
to return to the application. Alternatively, DPOJET can also be
accessed from Analyze > Jitter and Eye Analysis (DPOJET) > Select.
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Tutorial
In the Summary tutorial, the tutorial waveforms are recalled as Math waveforms
using the following setup:
■
dplus_50gs_18g_20m_pat1.wfm is recalled as Ref1 and
dminus_50gs_18g_20m_pat1.wfm as Ref2.
NOTE. Using Math Setup ( Select Math > Math Setup in the menu bar to view
the Math Setup dialog. For more details, refer to the “Math Equation Editor:
Controls in your oscilloscope online help), set .
■
ckplus_50gs_18g_20m_pat1.wfm is recalled as Ref3 and
ckminus_50gs_18g_20m_pat1.wfm as Ref4.
NOTE. Using Math Setup, set
Taking a period measurement
In this lesson, you will learn how to take a period measurement and view the
results. You can also learn the following tasks:
Setting up a Period
Measurement
■
Select a measurement and a source
■
Configure measurement
■
Take measurements
■
View results as plots or statistics
■
View reports
■
Return to the application
Follow these steps to take a period measurement:
1. To set the application to default values, click File > Recall Default Setup.
This is not necessary if you have just started the application.
2. To view the DPOJET application, select Analyze > Jitter and Eye Analysis
(DPOJET) > Select.
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3. Go to Select in the left navigation panel. Click Period in the Measurements
area. The application shows the measurement and source selection on the
right of the display. The current measurement selection is displayed as
Period1. The subsequent selections will be Period2, Period3 and so on. In this
example, Rt-EyeTutorial.wfm is recalled as Ref1 and is selected as source for
Period1. New measurements initially use the same source as the earlier
measurement, or the most recently used source.
4.
Click
or the row which lists the selected measurement to configure the
source. Select Ref1 for Period1. For more details, refer to Source setup.
5. Click Ref Levels Setup. The Configure Reflevel menu appears. For more
details, refer to Ref levels.
6. Click Configure in the left navigation panel of the main application window
to view the configure tabs. For more details, refer to Configuring
measurements.
7. Click Plots to view the available plots for the selected measurement. Select
Time Trend for Period. For more details, refer to Configuring time trend.
8. Click Single to run the application. When complete, the result statistics is
shown in the results tab. The plots are displayed as shown:
NOTE. You can log result , to a .csv file and to a .wfm file.
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Taking a TIE measurement
For jitter application, use the PLL TIE measurement. The steps to take a TIE
measurement are:
1. To set the application to default values, click File > Recall Default Setup.
This is not necessary if you have just started the application.
2. Go to Select in the left navigational panel. Click Jitter tab to select TIE in
the Measurements area. The application shows the measurement and source
selection on the right of the display. In this example, Rt-EyeTutorial.wfm is
recalled as Ref1 and is selected as source for TIE1.
3.
Click
or the row which lists the selected measurement to configure the
source. Select Ref1 for TIE1. For more details, refer to Source setup.
4. Click Ref Levels Setup in the source configuration dialog. The Configure
Reflevel menu appears. For more details, refer to Ref levels.
5. Click Configure in the left navigation panel to view the configure tabs. For
more details, refer to Configuring measurements.
1. Click Plots to view the available plots for the selected measurement. Select
Time Trend and Spectrum plots for TIE measurement. For more details, refer
to Configure plots.
2. Click Single to run the application. When complete, the result statistics is
shown in the results tab. The plots are displayed as follows:
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NOTE. You can log result Statistics, Measurement data points to a .csv file and
Worst case waveforms to a .wfm file.
Taking an eye height and width measurement
For signal integrity application, use the Eye Height and Width measurements.
1. Select Analyze > Jitter and Eye Analysis (DPOJET) > Select to run the
DPOJET application.
2. Go to Select in the left navigation panel. Click Eye tab to select Height and
Width measurement. In this example, Rt-EyeTutorial.wfm is recalled as Ref1
and is selected as source for Height1 and Width1.
3. Select Ref1 as source for Height and Width measurements. For more details,
refer to Source setup.
4. Click Plots to view the available plots for the selected measurement. Select
Eye Diagram for Height measurement.
5. Select Eye diagram Plot type and click Configure to turn on the Mask in the
Configure Eye Diagram for Eye Height dialog. For more details, refer to the
Configuring eye diagram plot for eye height.
6. Select Histogram plot for Width measurement.
7. Click Single to run the application. When complete, the result statistics is
shown in the results tab.
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8. The Plot summary window is displayed as shown in the following figure:
NOTE. You can log result Statistics, Measurement data points to a .csv file and
Worst case waveforms to a .wfm file.
Summary tutorial
For a summary tutorial, the following example is considered:
Case 1: Period measurement with Low pass filters to show SSC profile:
1. Select Analyze > Jitter and Eye Analysis (DPOJET) > Select to run the
DPOJET application. For more details on waveforms recalled on Math1,
Refer Recalling a waveform file.
2. Select Period measurement on Math1.
3. Click Configure. In the Filters configuration tab, select 2nd order low pass
filter and specify the cut-off frequency as 33 kHz. (F2= Fbaud/1667).
4. Go to Plots. Select Time Trend for Period measurement.
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5. Click Single to run the application. When complete, the result statistics is
shown in the results tab. The Time Trend plot is as shown.
Case 2: A pair of TIE for showing jitter integration caused by SSC and the effect
of a high pass filter on SSC spectrum plots:
1. Click Jitter to select TIE measurement.
2. Select Math1 as the source for both TIE1 and TIE2.
3. Click Configure. Do the following settings for TIE1 and TIE2 in the Filters
configuration tab:
■
Select “No Filter” for TIE1.
■
Select 2nd order High Pass filter for TIE2. In this example, the F1 cut-off
frequency is set to 1 GHz.
4. Go to Plots. Select Time Trend for both TIE1 and TIE2.
5. Select Spectrum plot for both TIE1 and TIE2.
6. Click Single to run the application. When complete, the result statistics is
shown in the results tab.
208
DPOJET Printable Application Help
Tutorial
7. A Plot Summary window shows Time Trend plots for TIE1, TIE2 and
Spectrum plots for TIE1, TIE2.
NOTE. You can log result Statistics, Measurement data points to a .csv file and
Worst case waveforms to a .wfm file.
Stopping the tutorial
If you need more than one session to complete the tutorial lessons, you can stop
the tutorial and return to it later.
To save the application setup, refer to Saving a setup file. To exit the DPOJET
application, click
present at the right corner of the application.
Returning to the tutorial
To return to the tutorial setup, you can start the application and then recall the
saved setup. To recall the application setup, refer to Recalling a saved setup file.
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Tutorial
210
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Parameters
About parameters
This section describes the DPOJET application parameters and includes the menu
default settings. Refer to the user manual for your oscilloscope for operating
details of other controls, such as front-panel buttons.
The parameter tables list the selections or range of values available for each
option, the incremental unit of numeric values, and the default selection or value.
Refer to the GPIB section for a complete list of the GPIB Command Syntax. The
topics include a complete list of the GPIB commands along with the arguments,
variables, and variable values that correspond to the DPOJET parameters.
Measurement select parameters
The Measurement Select includes the following measurement categories:
■
Period/Freq: Frequency, Period, CC–Period, N–Period, Pos Width, Neg
Width, +Duty Cycle, –Duty Cycle, +CC–Duty, and –CC–Duty.
■
Jitter: TIE, RJ, DJ, PJ, DDJ, DCD, RJ–δδ, DJ–δδ, TJ@BER, J2, J9, SRJ, F/
N, RJ(h), RJ(v), PJ(h), PJ(v), Jitter Summary, and Phase Noise.
■
Noise: RN, RN(v), RN(h), DN, DDN, DDN(1), DDN(0), PN, PN(v), PN(h),
NPN, TN@BER, Unit Amplitude and Noise Summary.
■
Time: Rise Time, Fall Time, High Time, Low Time, Setup, Hold, Rise Slew
Rate, Fall Slew Rate, Skew, SSC Profile, SSC Mod Rate, SSC Freq Dev,
SSC Freq Dev Min, SSC Freq Max, and tCMD-CMD.
■
Eye: Height, Width, Mask Hits, Autofit Mask Hits, Width@BER,
Height@BER, Q-Factor, Eye High, Eye Low, and AutoFit Mask Hits.
DPOJET Printable Application Help
211
Parameters
■
Ampl: High, Low, DC Common Mode, AC Common Mode, High–Low, T/
nT Ratio, Overshoot, Undershoot, V–Diff –Xovr, Cycle Min, Cycle Max,
and Cycle Pk-Pk.
■
Standard: Standard-specific measurements are as follows:
■
DDR: DDR Setup–SE, DDR Setup–Diff, DDR Hold–SE, DDR Hold–
Diff, DDR tCK(avg), DDR tCH(avg), DDR tCL(avg), DDR tERR(n),
DDR tERR(m–n), DDR tRPRE, DDR tWPRE, DDR tPST, DDR
tJIT(duty), DDR tJIT(per), DDR Over Area, DDR VID(ac), DDR Under
Area, DDR tDQSS, GDDR5 tBurst-CMD, GDDR5 tCKSRE, GDDR5
tCKSRX, DDR2 tDQSCK, DDR3 Vix(ac).
■
PCI Express: PCIe T-Tx-Diff-PP, PCIe T-TX, PCIe T-Tx-Fall, PCIe
Tmin-Pulse, PCIe DeEmph, PCIe T-Tx-Rise, PCIe UI, PCIe Med-MxJitter, PCIe T-RF-Mismch, PCIe MAX-MIN Ratio (Custom name is
PCIe VRX-MAX-MIN Ratio), PCIe SSC FREQ DEV, PCIe SSC
PROFILE, PCIe AC Common Mode.
■
USB 3.0 Essentials: USB VTx-Diff-PP, USB TCdr-Slew-Max,
USBTmin-Pulse-Tj, USB Tmin-Pulse-Dj, USB SSC MOD RATE, USB
SSC FREQ DEV MAX, USB SSC FREQ DEV MIN, USB SSC
PROFILE, USB UI, USB AC Common Mode.
You can set the Source option as any of the following waveforms: Ch1, Ch2,
Ch3, Ch4, Ref1, Ref2, Ref3, Ref4, Math1, Math2, Math3, Math4, B1, B2, B3,
B4, B5, B6, B7, B8, B9, B10, B11, B12, B13, B14, B15, or B16 (bus source
types are applicable for bus measurements only).
Table 75: Source parameters
212
Option
Parameters
Default
Source1
Ch1-Ch4, Math1-Math4, Ref1- Ch1
Ref4
Source1
B1–B16
Source2
Ch1-Ch4, Math1-Math4, Ref1- Ch2
Ref4
User should configure
DPOJET Printable Application Help
Parameters
Autoset parameters
The Configure Source Autoset includes the following command buttons:
■
Vert Scale
■
Horiz Res
■
Vert & Horiz
■
Undo
Ref level menu parameters
The Configure Ref Level menu parameters includes the following command
buttons:
Autoset Ref Levels
Parameters
■
Autoset
■
Setup
Option
Parameters
Source
Ch1-Ch4, Ref1-Ref4, Math1Math4
Autoset
Set, Clear
Set
Rise High
–20 V to 20 V
1V
Rise Mid
–20 V to 20 V
0V
Rise Low
–20 V to 20 V
–1 V
Fall High
–20 V to 20 V
1V
Fall Mid
–20 V to 20 V
0V
Fall Low
–20 V to 20 V
–1 V
Hysteresis
0 to 10 V
30 mV
Option
Parameters
Default setting
Base Top Method
■
Min-Max
■
Low-High Histogram (Full
Waveform)
■
Low- High Histogram
(Center of Eye)
■
Auto
Default setting
Auto
Rise High
1 to 99%
90%
Rise Mid
1 to 99%
50%
Rise Low
1 to 99%
10%
Fall High
1 to 99%
90%
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Parameters
Option
Parameters
Default setting
Fall Mid
1 to 99%
50%
Fall Low
1 to 99%
10%
Hysteresis
0 to 50%
3%
Preferences parameters
The Analyze > Jitter and Eye Analysis (DPOJET) > Preferences includes the
following tabs:
■
General
■
Measurement
■
Jitter Decomp
■
Path Defaults
Option
Parameters
Default setting
Horizontal Display Units
Seconds, Unit Intervals
Seconds
Vertical Display Units
Volts, Unit Amplitude
Volts
Default Image Type
PNG, JPG, BMP
PNG
Notifier Duration
2 to 20 s
5s
Limit Rise/Fall measurements
to transition bits only
Set, Clear
Clear
Enable high-performance eye
rendering
Set, Clear
Set
Halt free-run on a limit failure
for any measurement
Set, Clear
Clear
Waveform Interpolation Type
Linear, Sin(x)/x
Linear
Analysis Method
Jitter Only, Jitter + Noise
Jitter Only
Dual Dirac Model
Fibre Channel, PCI/FB-DIMM
PCI/FB-DIMM
Loc RJ Value
1fs to 1s
1ps
Jitter Separation Model
Spectral Only, Spectral + BUJ
Spectral Only
Minimum # of UI for BUJ
Analysis
10K to 9M
200k
Browser
C:\%USERPROFILE%
\Tektronix\TekApplications
\DPOJET\Images 1
General
Measurement
Jitter Decomp
Path Defaults
Default image export directory
214
DPOJET Printable Application Help
Parameters
Option
Parameters
Default setting
Default logging export directory Browser
C:\%USERPROFILE%
\Tektronix\TekApplications
\DPOJET\Logs1
Default report output directory
C:\%USERPROFILE%
\Tektronix\TekApplications
\DPOJET\Reports1
Browser
Deskew parameters
The Analyze > Jitter and Eye Analysis (DPOJET) > Deskew includes the
following command buttons:
■
Perform Deskew
■
Summary
Option
Parameters
Default setting
Source
Ch1, Ch2, Ch3, Ch4
Ch1
Mid
–20 V to 20 V
0V
Hysteresis
0 to 10 V
30 mV
Source
Ch1, Ch2, Ch3, Ch4
Ch2
Mid
–20 V to 20 V
0V
Hysteresis
0 to 10 V
30 mV
Edges
Rise, Fall, Both
Rise
Max Value
–24.9 ns to 25 ns
1 ns
Min Value
–25.0 ns to 24.9 ns
–1 ns
Reference Channel
Channel to be Deskewed
Deskew Range
1
%USERPROFILE% represents your user location.
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Parameters
Data logging parameters
The application includes the following Log menus:
■
Statistics
■
Measurement
■
Worst Case
Option
Parameters
Default
Select Target Measurements
Set, Clear
Set
Log Statistics
Off, On
Off
Data Log File
Browser
C:\%USERPROFILE%
\Tektronix\TekApplications
\DPOJET\Logs\Statistics 2
Select Target Measurements
Set, Clear
Set
Log Measurements
Off, On
Off
Folder
Browser
C:\%USERPROFILE%
\Tektronix\TekApplications
\DPOJET\Logs\Measurements2
Select Target Measurements
Set, Clear
Set
Log Worst Case Waveforms
Off, On
Off
Folder
Browser
C:\%USERPROFILE%
\Tektronix\TekApplications
\DPOJET\Logs\Waveforms2
Statistics
Measurement
Worst Case
2
216
%USERPROFILE% represents your user location.
DPOJET Printable Application Help
Parameters
Control panel parameters
The Control Panel menu includes the following command buttons:
■
Clear
■
Recalc
■
Single
■
Run
■
Show Plots
NOTE. Show Plots appears in the control panel only when one or more plots are
selected.
Configure measurement parameters
Bit config parameters
The Eye configure menu has the following parameters:
Option
Parameters
Default setting
Bit Type
All Bits, Transition, NonTransition
All Bits
Browser
C:\Users\Public\Tektronix
\TekApplications\DPOJET
\Masks
1 to 100%
50%
Mean, Mode
Mean
Start, End, # of Bins
50%, 50%, 1
Mask
3
Measure the Center of the Bit
Method4
Measurement range (% UI)
3
4
5
5
4
The Mask selector is available only for Mask Hits measurement.
Available only for High, Low, and High–Low measurements.
Available only for Height@BER measurement
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Parameters
Edges parameters
The Edges configure menu depends on the measurement selected.
Period, Freq, TIE, RJ, RD-dd, TJ@BER, DJ, DJ-dd, PJ, J2, J9, SRJ,
Width@BER, RJ(h), RJ(v), PJ(h), PJ(h)
Option
Parameters
Default setting
Signal Type
Clock, Data, Auto
Auto
Clock Edge
Rise, Fall, Both
Rise
Option
Parameters
Default setting
Signal Type
Clock, Data, Auto
Auto
Clock Edge
Rise, Fall, Both
Rise
N=
1 to 1M
6
Edge Increment
1, 10 K
1
N-Period
Positive and Negative duty cycle, CC Period
Option
Parameters
Default setting
Clock Edge
Rise, Fall, Both
Rise
Option
Parameters
Default setting
Active Edge
Rise, Fall, Both
Rise
Upper Frequency
0 to 1 T
1 MHz
Lower Frequency
0 to 1 T
0 Hz
Option
Parameters
Default setting
Signal Type
Clock, Data, Auto
Auto
Option
Parameters
Default setting
Signal Type
Clock, Data, Auto
Auto
Clock Edge
Rise, Fall, Both
Rise
N=
2, 4, 8
2
Phase noise
Noise Integration Limits
DCD
F/N
Skew
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DPOJET Printable Application Help
Parameters
Option
Parameters
Default setting
From Edge
Rise, Fall, Both
Both
To Edge
Same as From, Opposite as
From
Same as From
Option
Parameters
Default setting
Clock Edge (Source 1)
Rise, Fall, Both
Rise
Data Edge (Source 2)
Rise, Fall, Both
Both
Option
Parameters
Default setting
From Level
Mid, Low
Low
To Level
High, Mid
High
Slew Rate Technique
Nominal Method, DDR Method Nominal Method
Setup and Hold
Rise slew rate
Fall slew rate
Option
Parameters
Default setting
From Level
High, Mid
High
To Level
Mid, Low
Low
Slew Rate Technique
Nominal Method, DDR Method Nominal Method
Time outside level
Option
Parameters
Default setting
Level
High, Low, Both
High
High Ref Voltage
User selectable
0V
Option
Parameters
Default setting
Ref Voltage
–100 V to 100 V
0V
Option
Parameters
Default setting
Main Edge
Rise, Fall, Both
Both
Overshoot/Undershoot
V-Diff-Xovr
CrossOver
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219
Parameters
Option
Parameters
Default setting
Main Edge
Rise, Fall, Both
Both
DDR tCH(avg) and DDR tCL(avg)
Option
Parameters
Default setting
Window Size
200 to 1M
200
Option
Parameters
Default setting
Clock Edge
Rise, Fall
Rise
Maximum
6 to 50
The value varies for different
DDR generations. For example,
for DDR (6–10) measurement,
the maximum default is 10.
Minimum
2 to 50
The value varies for each DDR
generation. For example, for
DDR (6–10) measurement, the
minimum default is 6.
Window Size
200 to 1M
200
Option
Parameters
Default setting
Clock Edge
Rise, Fall
Rise
Number of Periods
2 to 50
The value varies for each DDR
generation. For example, for
DDR tERR(7per) measurement,
the default value is 7.
Window Size
200 to 1M
200
DDR tERR(m-n)
Number of Periods
DDR tERR(n)
DDR tJIT(per), DDR tCK(avg) and DDRtJIT(duty)
220
Option
Parameters
Default setting
Clock Edge
Rise, Fall
Rise
Window Size
200 to 1M
200
DPOJET Printable Application Help
Parameters
Clock recovery
parameters
The Clock recovery configure menu depends on the clock recovery method being
selected.
PLL Clock recovery method parameters.
Option
Parameters
Default setting
PLL Model
Type I, Type II
Type I
Standard: b/s
IBA2500: 2.5G, PCI-E: 2.5G,
PCI-E: 2.5G
PCI_E_GEN2: 5.0G
FC133: 132.8M, FC266:
265.6M, FC531: 531.2M,
FC1063: 1.063G,
FC2125:2.125G,
SerATAG1:1.5G,
SerATAG2:3.0,
SerATAG3:6.0G
USB 3.0: 5.0G
1394b S400b: 491.5M, 1394b
S800b: 983.0M, 1394b S1600b:
1.966G
GB Ethernet: 1.25G
100BaseT:125M
OC1:51.8M, OC3:155M,
OC12:622M, OC48:2.488G,
FC4250:4.25G, FC8500:8.5G
IBA_GEN2: 5.0G
FBD1:3.2G, FBD2: 4.0G, FBD3:
4.8G
XAUI: 3.125G, XAUI_GEN2:
6.25G
SAS15:1.5G (no SSC), SAS3:
3.0G (no SSC), SAS6: 6.0G (no
SSC), SAS12: 12.0G (no SSC)
SAS15:1.5G (SSC), SAS3:
3.0G (SSC), SAS6: 6.0G
(SSC), SAS12: 12.0G (SSC)
RIO125: 1.25G, RIO250: 2.5G,
RIO3125: 3.125G
PLL Standard BW
Damping
6
0.5 to 2
700 m
1 to 2.5 GHz
1.5 MHz
PLL Model
Type I, Type II
Type I
Loop BW
1 to 2.5 GHz
1.5 MHz
Loop BW
PLL Custom BW
6
Enabled only for Type II PLL models.
DPOJET Printable Application Help
221
Parameters
Constant clock recovery method parameters.
Option
Parameters
Default setting
First Acq, Every Acq
Every Acq
First Acq, Every Acq
Every Acq
1 Hz to 25 GHz
2.5 GHz
Constant Clock-Mean
Auto Calc
Constant Clock-Median
Auto Calc
Constant Clock-Fixed
Clock Frequency
Explicit clock recovery method parameters.
Option
Parameters
Default setting
Explicit Clock-Edge/Explicit Clock-PLL
Clock Source
Ch1-Ch4, Ref1-Ref4, Math1Math4
Ch2
Clock Edge
Rise, Fall, Both
Both
Clock Multiplier
1 to 1 K
1
Advanced clock recovery configuration parameters.
Option
Parameters
Default setting
PLL Custom BW/PLL Standard BW/ Constant Clock-Mean/Constant Clock-Median
Nominal Data Rate
Auto, Manual
Auto
Bit Rate
0 b/s to 100 Gb/s
Auto TBD
Manual 2.5 Gb/s
Known Data Pattern
On, Off
Off
Pattern Filename
Browse
C:\Users\Public\Tektronix
\TekApplications\DPOJET
\Patterns
Nominal Clock Offset Relative
to Data
Auto, Manual
Manual
Recalculate
Every acquisition, When
required
When required
PLL Method
Type I,Type II
Type I
Damping
0.5 to 2
700 m
Loop B/W
1 Hz to 2.5 GHz
1.5 MHz
Nominal Clock Offset Relative
to Data
Auto, Manual (-1s to 1s)
Manual
Recalculate
When required, Every
acquisition
When required
Explicit Clock: Edge
Explicit Clock:PLL
222
DPOJET Printable Application Help
Parameters
SSC parameters
The Spread Spectrum Clock menu has the following parameters:
Option
Parameters
Default setting
Auto
Determined by instrument
TBD
Manual
User selectable
2.5 GHz
Nominal frequency
RJ-DJ analysis parameters
The RJ-DJ configure menu has the following parameters:
Option
Parameters
Default setting
Pattern Detection
Auto, Manual
Auto
Pattern Type
Repeating, Arbitrary
Auto TBD
Manual Repeating
2 UI to 1M UI
2 UI
2 to 24 UI for Jitter Only
2 to 17 UI for Jitter + Noise
10 UI
2 to 18
12
Pattern Detection/Control
Pattern Length
7
8
Window Length
Target BER
BER = 1E-?
RN-DN analysis
parameters
9
The RN-DN configure menu has the following parameters:
Option
Parameters
Default setting
Pattern Detection
Auto, Manual
Auto
Pattern Type
Repeating, Arbitrary
Auto TBD
Manual Repeating
2 UI to 1M UI
2 UI
2 to 17 UI
10 UI
2 to 18
12
Pattern Detection/Control
Pattern Length 7
Window Length
8
Target BER
BER = 1E-?
7
8
9
10
10
Only for Repeating Patterns.
Only for Arbitrary Patterns.
Only for TIE, TJ@BER, and Width@BER measurements.
Only for TN@BER.
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Parameters
Filters parameters
The Filter configure menu has the following parameters:
Option
Parameters
Default setting
Filter Spec
No Filter, 1st order, 2nd order,
3rd order
No Filter
Freq (F1)
10 Hz to 1 THz
1 kHz
Filter Spec
No Filter, 1st order, 2nd order,
3rd order
No Filter
Freq (F2)
10 Hz to 1 THz
1 kHz
High Pass (F1)
Low Pass (F2)
Advanced filter configure parameters. The Advanced Filter Configuration includes
the following parameters:
Bus state
Option
Parameters
Default setting
Ramp Time
0/F to 10/F
2/F
Blanking Time
0/F to 10/F
4/F
The Bus State configure menu has the following parameters:
Table 76: Bus state options
Option
Parameters
Default setting
Use symbol file
On, Off
On
Enter pattern
On, Off
Off
Symbol
MODE_REG, REFRESH,
PRECHARGE, ACTIVATE,
WRITE, READ, SRX,
DESELECT, SRE, PDE
PDE
Measure at
Clock Edge, Start, Stop
Clock Edge
Clock Source
Ch1, Ch2, Ch3, Ch4, Math1,
Math2, Math3, Math4, Ref1,
Ref2, Ref3, Ref4
Ch2
Clock Polarity
Rising, Falling
Rising
From Symbol
MODE_REG, REFRESH,
PRECHARGE, ACTIVATE,
WRITE, READ, SRX,
DESELECT, SRE, PDE
MODE_REG
To Symbol
MODE_REG, REFRESH,
PRECHARGE, ACTIVATE,
WRITE, READ, SRX,
DESELECT, SRE, PDE
MODE_REG
Clock Edge Settings
224
DPOJET Printable Application Help
Parameters
General parameters
Option
Parameters
Default setting
To Symbol
MODE_REG, REFRESH,
PRECHARGE, ACTIVATE,
WRITE, READ, SRX,
DESELECT, SRE, PDE
MODE_REG
Measure at
Clock Edge, Start, Stop
Clock Edge
The General configure menu has the following parameters:
Option
Parameters
Default setting
Measurement Range Limits
Off, On
Off
Maximum and minimum values vary for different measurements. For more
details, refer to Measurement range limit values.
Global parameters
The Global configure menu has the following parameters:
Option
Parameter
Default setting
Off, Zoom, Cursors
Off
Off, On
Off
Gating
Gating
Qualify
Qualify
Qualify With Logic
Source
Ch1-Ch4, Ref1-Ref4, Math1Ch1
Math4, Search0-Search8, Burst
Search
Mid
–20 V to 20 V
OV
Hysteresis
0 to 10 V
30 mV
Active
High, Low
High
Off, On
Off
Limits By
Population, Acquisitions
Acquisitions
Limit
1 to 231
1K
Stop Condition
Each Measurement, Last
Measurement
Each Measurement
Population
Population
Population Limit
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Parameters
Plots
Histogram plot parameters
The Histogram plot has Autoset as the command button.
Option
Parameters
Default setting
Vertical Scale
Log, Linear
Linear
25, 50, 100, 250, 500
250
Auto Scale
Set, Clear
Set
Center
–1 ms to 1 Ts
100 ns
Span
1 s to 1 Ts
4 ns
Number of Bins
Resolution
Horizontal Scale
Eye diagram plot
parameters
The Eye Diagram plot has the following parameters:
Option
Parameters
Default setting
Mask
On, Off
Off
Browser
C:\Users\Public\Tektronix
\TekApplications\DPOJET
\Masks
Auto Scale
Set, Clear
Set
Resolution
2.00E–13 to 2.00E–08
1.00E–12
Horizontal Scale
Spectrum plot parameters
226
Superimpose Reference Clock Set, Clear
Eye (if available)
Clear
Ref Clock Alignment
Auto
Auto, Centre and Left
The Spectrum plot has the following parameters:
Option
Parameters
Default setting
Vertical Scale
Log, Linear
Log
Base
–20 to 15
–15
Horizontal Scale
Log, Linear
Linear
Mode
Normal, Average, Peak Hold
Normal
DPOJET Printable Application Help
Parameters
Time trend plot
parameters
Phase noise plot
parameters
The Time Trend plot has the following parameters:
Option
Parameters
Default setting
Mode
Vector, Bar
Vector
The Phase Noise plot has the following parameters:
Option
Parameters
Default setting
–200 to 0
–170
Vertical Position
Baseline
Bathtub plot parameters
The Bathtub plot has the following parameters:
Option
Parameters
Default setting
Vertical Scale
Log, Linear
Log
Minimum displayed BER= 1E-? 2 to 18
X-Axis Unit
Transfer function plot
parameters
1
1
Unit Interval, Seconds
14
Unit Interval
The Transfer Function plot has the following parameters:
Option
Parameters
Default setting
Vertical Scale
Log, Linear
Log
Horizontal Scale
Log, Linear
Log
Mode
Normal, Average
Average
Applicable for Log and Linear scale only.
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Parameters
Composite jitter histogram
plot parameters
The Composite Jitter Histogram plot has the following parameters:
Option
Parameters
Default setting
Vertical Scale
Log, Linear
Linear
25, 50, 100, 250, 500
250
Number of Bins
Resolution
Noise bathtub plot
parameters
The noise bathtub plot has the following parameters:
Option
Parameters
Default setting
Horizontal Scale
Log, Linear
Log
Minimum displayed BER = 1E-? 2 to 18
Y-Axis Unit
BER Eye contour plot
paramters
14
Unit Amplitude, Volts
Unit Amplitude
The BER eye contour plot has the following parameters:
Option
Parameters
Default setting
Mask
On, Off
Off
Browser
C:\Users\Public\Tektronix
\TekApplications\DPOJET
\Masks
1E-6, 1E-9, 1E-12, 1E-15,
1E-18, Target BER (1E-12)
All BER contours to display will
be selected.
BER contours to display
Composite noise
histogram plot parameters
2
The composite noise histogram plot has the following parameters:
Option
Parameters
Default setting
Horizontal Scale
Log, Linear
Linear
Noise Components
TN, RN+NPN, PN, DDN(0),
DDN(1)
All noise components will be
selected
25, 50, 100, 250, 500, 2000,
Maximum
250
Number of Bins
Resolution
2
228
Applicable for Log and Linear scale only.
DPOJET Printable Application Help
Parameters
BER Eye plot parameters
Correlated Eye plot
parameters
PDF Eye plot parameters
The BER eye plot has the following parameters:
Option
Parameters
Default setting
BER contours to display
1E-6, 1E-9, 1E-12, 1E-15,
1E-18, Target BER (1E-12)
All BER contours to display will
be selected.
The Correlated eye plot has the following parameters:
Option
Parameters
Default setting
BER contours to display
1E-6, 1E-9, 1E-12, 1E-15,
1E-18, Target BER (1E-12)
All BER contours to display will
be un-selected.
The PDF eye plot has the following parameters:
Option
Parameters
Default setting
BER contours to display
1E-6, 1E-9, 1E-12, 1E-15,
1E-18, Target BER (1E-12)
All BER contours to display will
be selected.
Reports
The Reports menu has the following command buttons:
■
Save
■
Save As
■
Append
■
View
■
Add/Edit comments
Option
Parameters
Default setting
Auto increment report name if
duplicate
Set, Clear
Set
Display units in separate
column
Set, Clear
Clear
View report after generating
Set, Clear
Set
Display units in separate
column
Set, Clear
Clear
Include pass/fail results
summary
Set, Clear
Set
Include detailed results
Set, Clear
Set
Include plot images
Set, Clear
Set
Content To Save
DPOJET Printable Application Help
229
Parameters
230
Option
Parameters
Default setting
Include setup configuration
Set, Clear
Set
Include user comments
Set, Clear
Set
Include complete application
configuration
Set, Clear
Set
Save Waveform file(s) along
with report
Set, Clear
Clear
Report Name
Browser
C:\%USERPROFILE%
\Tektronix\TekApplications
\DPOJET\Reports, where
%USERPROFILE% represents
your user location.
DPOJET Printable Application Help
Reference
Progress bar status messages
Function/Measurement
module
Status/Message
Description
Autoset-Source Autoset
VertAuto-Chx
Vertical autoset for Chx is going
on.
Autoset-Source Autoset
HorizAuto-Chx
Horizontal autoset for Chx is
going on.
Autoset-Source Autoset
Zooming Horiz
Zooming the horizontal scale
after horizontal autoset.
Autoset-Ref Level Autoset
RefAuto-Chx
Reference level autoset for Chx
is going on.
Autoset-Ref Level Autoset
RefAuto-Refx
Reference level autoset for
Refx is going on.
Autoset-Ref Level Autoset
RefAuto-Mathx
Reference level autoset for
Mathx is going on.
Sequencing
Sequencing
Refers to the measurement
setup-edge extraction.
Measurement Name
Running the measurement
specified by name.
Plotting
Plotting is started.
Bathtub
Creating Bathtub plot.
Spectrum
Creating spectrum plot.
Time Trend
Creating time trend plot.
Histogram
Creating Histogram plot.
Transfer Func
Creating Transfer Function plot.
Eye Mask Hits
Creating Eye Diagram plot.
Eye Height
Creating Eye Diagram plot.
Data Array
Creating Data Array plot.
Phase Noise
Creating Phase noise plot.
Edge Extraction
Finding Edges
Extracting Edges from signal
waveform.
Clock Data Recovery
Recovery Clk
Clock and Data recovery.
Worst case logging
Saving WC Wfm
Logging the worst case
waveform.
Trigger
Slow Trigger
Waiting for trigger/trigger not
available.
Measurements Name
Progress Bar Display
Plots
DPOJET Printable Application Help
231
Reference
232
Function/Measurement
module
Status/Message
Amplitude High Low
Ampl High–Low
Amplitude HighV
Amp High
Amplitude LowV
Ampl Low
CMV
Common Mode
DCD
DCD
DDJ
DDJ
DiffXovrV
V-Diff-Xovr
DJ
DJ
DJδδ
DJ–δδ
EdgeExtractor
Edge Extractor
EyeHeight
Eye Height
EyeHeightBER
Eye Height@BER
EyeMaskHits
Eye Mask Hits
EyeWidth
Eye Width
EyeWidthBER
Eye Width@BER
FallTime
Fall Time
Frequency
Freq
HighTime
High Time
Hold
Hold
LowTime
Low Time
NegativeDutyCycle
–Duty Cycle
NegativeDutyCycleCycle
–CC–Duty
NegativeWidth
Neg Width
NPeriod
N–Period
PerCycleCycle
CC–Period
Period
Period
PhaseNoise
Phase Noise
PJ
PJ
PositiveDutyCycle
+Duty Cycle
PositiveDutyCycleCycle
+CC–Duty
PositiveWidth
Pos Width
RiseTime
Rise Time
RJ
RJ
RJδδ
RJ–δδ
Setup
Setup
Skew
Skew
TIE
TIE
TJ
TJ@BER
Description
DPOJET Printable Application Help
Reference
Function/Measurement
module
Status/Message
TNTRatio
T/nT Ratio
TJ@BER
TJ
NPJ
NPJ
RJ(H)
RJH
RJ(V)
RJV
PJ(H)
PJH
PJ(V)
PJV
SRJ
SRJ
J2_
J2
J9_
J9
F/N
F_N
RN
RN
RN (v)
RNV
RN (h)
RNH
DN
DN
DDN
DDN
DDN0
DDN0
DDN1
DDN1
PN
PN
PN (v)
PNV
PN (h)
PNH
NPN
NPN
TN@BER
TN
Unit Amplitude
UA
DPOJET Printable Application Help
Description
233
Reference
Breakdown of jitter (Jitter map)
The breakdown of jitter into components such as RJ, PJ and DDJ is model-based.
This means that a suitable mathematical model is proposed for the overall jitter,
consisting of various jitter components. The components are separable from each
other based on observable characteristics, and the rules by which these
components combine to form an overall jitter distribution are based on wellunderstood mathematical principles.
The model used by DPOJET is hierarchical, and is represented by a jitter map. To
view the jitter breakdown map, follow the steps:
■
Click Select > Jitter
■
Click the information icon (
) in the upper right corner of the panel.
NOTE. If noise measurements are enabled, the Jitter tab is displayed as Jitter/
Noise and buttons at the top of the tab allow selection of Jitter or Noise
measurements. Select the jitter button (
) to display the jitter measurements.
DPOJET displays one of the two different jitter maps depending on the global
configuration:
■
Spectral only (default): A simpler map that does not include NPJ and BUJ
categories is used when the decomposition method is set to 'Spectral only'.
This offers simpler and faster processing and gives accurate results when
crosstalk is not present (and often even when it is present).
■
Spectral + BUJ: This decomposition method offers an additional model
component (Non-Periodic Jitter or NPJ). This jitter model is more accurate
when certain types of crosstalk are present. The disadvantage of using this
map is that more statistics (that is, a higher population of unit intervals) must
be acquired before results can be produced. This may require longer record
length, multiple acquisitions, or both.
By clicking the radio buttons in the upper left corner of the map window, you can
switch between the two jitter models and their corresponding maps. Once a
model has been selected, you can add jitter measurements by clicking directly on
the buttons embedded in the map, or dismiss the map and click on the
conventional buttons in the main control window.
234
DPOJET Printable Application Help
Reference
Figure 3: Jitter map - Spectral Only
Figure 4: Jitter map - Spectral + BUJ
DPOJET Printable Application Help
235
Reference
Related topics
DPOJET options levels
Separation of Non-Periodic Jitter (NPJ)
Breakdown of noise (Noise map)
The breakdown of noise into components such as RN and DN is model-based.
This means that a suitable mathematical model is proposed for the overall noise
measurements, consisting of various components. The components are separable
from each other based on observable characteristics, and the rules by which these
components combine to form an overall noise distribution are based on wellunderstood mathematical principles.
The model used by DPOJET is hierarchical, and is represented by a noise map.
To view the noise breakdown map, follow the steps:
■
Click Select > Jitter/Noise and select the noise measurement by radio button.
The Preference setup - Jitter Decomp allows you to enable or disable noise
measurements by changing the Analysis Method, if the noise measurement
option is available.
■
Click the information icon (
) in the upper right corner of the panel.
NOTE. If the tab is labeled 'Jitter' and the Jitter and Noise radio buttons are
absent, Noise measurements are currently disabled.
DPOJET displays one of the two different jitter maps depending on the global
configuration:
■
Spectral only (default): A simpler map that does not include NPN and BUN
categories is used when the decomposition method is set to 'Spectral only'.
This offers simpler and faster processing and gives accurate results when
crosstalk is not present (and often even when it is present).
■
Spectral + BUJ: This decomposition method offers an additional model
component (Non-Periodic Noise or NPN). This noise model is more accurate
when certain types of crosstalk are present. The disadvantage of using this
method is that more statistics (that is, a higher population of unit intervals)
must be acquired before results can be produced. This may require longer
record length, multiple acquisitions, or both.
By clicking the radio buttons in the upper left corner of the map window, you can
switch between the two decomposition models and their corresponding maps.
Once a model has been selected, you can add noise measurements by clicking
directly on the buttons embedded in the map, or dismiss the map and click on the
conventional buttons in the main control window.
236
DPOJET Printable Application Help
Reference
Figure 5: Noise map - Spectral Only
Figure 6: Noise map - Spectral + BUJ
DPOJET Printable Application Help
237
Reference
Related topics
DPOJET options levels
Separation of Non-Periodic Jitter (NPJ)
Error codes
238
Code
Description
E102
File does not exist
E103
DPOJET is not able to open the help file. In order to use the help file, please
reinstall DPOJET.
E104
Mask Hits measurement requires an Eye diagram plot but no more plots can
be assigned. Please remove a plot before adding a Mask Hits measurement.
E105
The maximum number of plots you can select is 4.
E106
No Spectrum plot data is available.
E107
This plot type is not configurable.
E109
The SSC PROFILE measurement requires an Time Trend plot but no more
plots can be assigned. Please remove a plot before adding a SSC PROFILE
measurement.
E202
The upper range must be greater than the lower range.
E400
A measurement failed to complete successfully.
W410
Number of edges are not sufficient for a measurement.
E411
In at least one zone, there are too few edges to complete a measurement.
E424
No edges or UI of the required type were found in the waveform. If this is not a
clock signal, check the Vref threshold and record length.
E425
No transitions of the selected Bit Type were found in the waveform.
E426
Result has 0 population since all measurement points fall within the PLL's
settling time. Either acquire a longer waveform, or increase the PLL's
bandwidth.
E500
The record lengths of the source waveforms differ. Please configure for
sources with equivalent record lengths.
E1001
Vertical Autoset Failed: Signal on Source x has extreme offset.
E1002
Vertical Autoset Failed: Amplitude of Source x is too small.
E1003
Vertical Autoset Failed: Amplitude or DC offset of Source x is too high.
E1004
Vertical Autoset Failed: No signal on Source x.
E1005
Vertical Autoset Failed: Signal on Source x exceeds top of scale.
E1006
Vertical Autoset Failed: Signal on Source x exceeds bottom of scale.
E1007
Vertical Autoset Failed: Signal on Source x is clipped on top.
E1008
Vertical Autoset Failed: Signal on Source x is clipped on bottom.
E1009
Vertical Autoset Failed: Measurement error ( ISDB error code = 6 ) on Source
x.
E1010
Vertical Autoset Failed: Measurement error ( ISDB error code = 7 ) on Source
x.
DPOJET Printable Application Help
Reference
Code
Description
W1011
A change to Source x vertical settings caused overload disconnect. Original
settings are restored and Source x is reconnected. Ignore oscilloscope
message.
E1012
Vertical Autoset Failed: None of the selected measurements use live sources
(Ch1-Ch4). Vertical autoset works for live sources only.
E1013
Vertical Autoset Failed: Invalid signal on Source x.
E1020
Horizontal Autoset Failed: None of the selected measurements use live
sources (Ch1-Ch4). Horizontal autoset works for live sources only.
E1021
Horizontal Autoset Failed: On Source x, cannot determine resolution of rising/
falling edges.
E1022
Horizontal Autoset Failed: Horizontal resolution is at the maximum.
E1026
Horizontal Autoset Failed: Source amplitude is too low.
E1027
Horizontal Autoset Failed: Signal is clipped at the top - positive clipping.
E1028
Autoset Failed: Signal is clipped at the bottom - negative clipping.
E1029
Horizontal Autoset Failed: Signal frequency is extremely low.
E1035
Oscilloscope has gone into invalid state. Please restart the system.
E1040
Autoset Failed: None of the live sources (Ch1-Ch4) selected.
W1051
Ref Level Autoset: Waveform for the source x is clipped.
W1053
Ref Level Autoset: Source amplitude is extremely low.
E1054
Ref Level Autoset: Error in setting reference levels.
E1055
Ref Level Autoset Failed: No waveform to measure.
E1056
Ref Level Autoset: Unstable Histogram for waveform on source x.
E1057
Ref Level Autoset: No selected source.
E1058
Ref Level Autoset Failed: Invalid signal on source x.
E1059
Ref Level Autoset Failed: High/Low Method measures High = Low on.
E1060
Ref Level Autoset Failed: Max/Min Method measures Max = Min on.
E1061
Since Digital Filters (DSP) Enabled, Maximum sampling rate has been
retained. To enable adaptive use of lower sampling rate, please choose
Analog Only under Vertical->Bandwidth Enhanced.
E1062
The maximum Record Length (RL) in autoset is restricted to 25M, set the RL
manually for > 25M.
E1063
The minimum Record Length (RL) in autoset is restricted to 500K, set the RL
manually for < 500K.
W1064
Ref Level Autoset: Unable to trigger.
E2001
The maximum number of measurements has been reached.
E2002
All the refs are used as sources by the measurements. Export to Ref is not
possible.
E2003
Ref ‘x’ is already used as a measurement source.
E2004
Ref ‘x’ is already used as a destination for other measurement.
E2005
No measurement(s) are selected. Export to Ref is not possible.
E2006
No results available to export to ref.
DPOJET Printable Application Help
239
Reference
240
Code
Description
E2007
There are no time trend results for the selected measurement(s).
E2008
No ref destination is selected. Results will not be exported to ref.
E3001
Could not open or create a log file. Please ensure that you have read/write
permission to access log folders and files.
E3002
The specified path is invalid (for example, the specified path is not mapped to
a drive).
E3003
The specified path, file name or both exceed the system defined length. For
example, on Windows-based platforms, the path name must be less than
248 characters and file names less than 260 characters.
E3004
The specified path directory is read-only or is not empty.
E3005
Please ensure that the file is currently not in use by other process and/or has
not exceeded the file size limit.
E3006
Invalid filename: Check whether the file name contains a colon (:) in the
middle of the string.
E3007
Select at least one measurement from the table before you save.
E3008
There are currently no results to save. Please run a measurement.
E3009
Current statistics is successfully saved at C:\%USERPROFILE%\Tektronix
\TekApplications\DPOJET\Logs\Statistics, where %USERPROFILE%
represents your user location.
E3010
Access to file/directory denied. Please ensure that the file/directory has read/
write permissions.
E3011
Mask Hits Measurements will not be selected as this feature is not available
for Mask Hits measurement.
E3012
Folder does not exist.
E4000
Not enough data points. Unable to render plot(s).
E4001
Internal measurement error. Please remove a measurement and try again.
E4002
Not enough data points for spectrum computation.
E4003
Due to high memory usage, only a portion of the waveform could be
processed. Please reduce your record length or the number of measurements.
E4004
An error occurred in the edge extraction process.
E4005
Qualifier: The record length and sample interval must match across the
waveforms.
E4006
A maximum of 4096 qualifier zones is supported. The entire waveform will not
be processed and hence partial measurement results are available.
E4007
Logic Qualifier enabled and no qualifier zones found.
W4008
The configured Ref voltage for Overshoot must be greater than or equal to the
mid autoset ref levels.
W4009
The configured Ref voltage for Undershoot must be lesser than or equal to the
mid autoset ref levels.
E4013
The configured Ref voltage must be greater than or equal to the mid autoset
ref levels.
E4014
The configured Ref voltage must be lesser than or equal to the mid autoset ref
levels.
DPOJET Printable Application Help
Reference
Code
E4015
Description
1
E4016
Not enough edges in the waveform for measurement calculation.
E4017
Qualifier not enabled and hence no qualifier zones found. Please enable the
qualifier.
E4018
The preamble is incomplete in all the qualifier zones.
E40191
The preamble is incomplete in one or more qualifier zones.
E4020
The postamble is incomplete in all the qualifier zones.
E40211
The postamble is incomplete in one or more qualifier zones.
E40221
Not enough samples present in the qualifier zones. Please increase the
sampling rate and reacquire the waveform.
E4023
The configured ref levels are not correct. The high ref level should be >= Mid
and Mid should be >= Low for both Rise and Fall slopes. Reconfigure the ref
levels and run the measurement.
E4024
Could not compute proper High and Low values.
W4025
The signal does not cross the configured Ref Voltage and hence the result
shows zero population. Please adjust the Ref voltage value.
W4026
Command Patterns were not found in the required order.
E4027
From Symbol not found in the acquisition.
E4028
To Symbol not found in the acquisition.
E4029
The configured High Ref voltage must be ≥ to the mid autoset ref levels.
E4030
The configured Low Ref voltage must be ≤ to the mid autoset ref levels.
E4031
The configured High Ref voltage must be ≥ to the mid autoset ref levels and
the configured Low Ref voltage must be ≤ to the mid autoset ref levels.
E4032
Set up the DDR Search and turn on the Qualifier to run this measurement.
E4033
Required command was not found after the burst.
E4034
Self Refresh Entry command is not registered in the current acquisition.
E4035
E5005
1
2
One or more qualifier zones had too few edges for measurement calculation.
Self Refresh Exit command is not registered in the current acquisition.
2
Occurs while running setup. Please make sure you have finished any previous
setup and closed other applications.
W5005
The path or file name exceeds the system limit of 260 characters.
W9005
Derating value calculated using single Slew Rate measurement value.
Displays the zone number for which the preamble/postamble fails.
This error occurs during DPOJET installation on a DPO/MSO oscilloscope. Delete the Installshield folder under C:
\Program files\Common Files and delete all files and folders under C:\Windows\Temp folder. Restart the installation
again.
DPOJET Printable Application Help
241
Reference
Code
Description
W9006
Derating value cannot be computed since the calculated Slew Rate is not
present in the derating table 3.
E9007
Derating Error 4.
Measurement range limit values
The following table lists the maximum and minimum values of all measurement
range limits:
NOTE. Measurement Range Limits are provided for each measurement under the
General configure tab of the DPOJET application. The range limits are turned
off by default. For two-source measurements such as Skew, Setup, Hold and a
few others, these range limits are always ON (OFF is disabled). In these cases,
the range limits are used by the algorithms to associate the valid edge of first
source to the valid edge of the second source.
Name
Measurement range limits (Max)
Measurement range limits (Min)
Default
Min
Default
Max
Min
Max
Period/Freq measurements
Period
1 ms
1 ks
0s
0s
1 ks
0s
CC–Period
1 ns
1s
1 fs
–1 ns
–1 fs
–1 s
Freq
10 GHz
50 GHz
1 MHz
1 MHz
50 GHz
1 MHz
N–Period
1 ms
1 ks
0s
0s
1 ks
0s
Pos Width/
Neg Width
10 ns
1 Ms
1 ps
1 ns
1 Ms
1 ps
+Duty
90 %
Cycle/–Duty
Cycle
100 %
0%
10 %
100 %
0%
+CC–Duty/ – 90 %
CC–Duty
100 %
100 %
10 %
100 %
0%
1 µs
–1 µs
–1 ns
1 µs
–1 µs
Jitter Measurements
TIE
3
1 ns
Signal Slew Rate value is outside the derating table (Example: If DDR2-800 MT/s tDS derating with a differential
probe has a DQS differential slew rate of 0.65 V/ns, this warning message is displayed as the derating table definition
starts from 0.8 V/ns).
Derating value is not supported (TBD) in the specification (Example: If the DQS differential slew rate is 2.0 V/ns and
the DQ slew rate is 0.7 V/ns, then the value is -(TBD).
4
Derating will not be applied for the above cases and the base limit will be displayed in the results table.
Slew Rate measurements used to calculate the derated value failed to Run as there are no sufficient edges on the Rise
and Fall slopes of the waveform.
Base measurement limits are not defined as per the specification.
242
DPOJET Printable Application Help
Reference
Name
Measurement range limits (Max)
Measurement range limits (Min)
Default
Max
Min
Default
Max
Min
RJ
1 ns
1 µs
0s
1 ns
1 µs
0s
RJ–δδ
1 ns
1 µs
0s
0s
1 µs
0s
TJ@BER
1 ns
1 µs
0s
0s
1 µs
0s
DJ
1 ns
1 µs
0s
0s
1 µs
0s
DJ–δδ
1 ns
1 µs
0s
0s
1 µs
0s
Phase Noise 1 ms
1 ms
0s
0s
1 ms
0s
DCD
1 ns
1 µs
0s
0s
1 µs
0s
DDJ
1 ns
1 µs
0 ns
0s
1 µs
0s
PJ
1 ns
1 µs
0s
0s
1 µs
0s
J2
1 ns
1 µs
0s
0s
1 µs
0s
J9
1 ns
1 µs
0s
0s
1 µs
0s
F/N
1 ns
1 µs
0s
0s
1 µs
0s
SRJ
1 ns
1 µs
0s
0s
1 µs
0s
RJ (h)
1 ns
1 µs
0s
0s
1 µs
0s
RJ (v)
1 ns
1 µs
0s
0s
1 µs
0s
PJ (h)
1 ns
1 µs
0s
0s
1 µs
0s
PJ (v)
1 ns
1 µs
0s
0s
1 µs
0s
Noise Measurements
RN
500mV
10V
-10V
-500mV
10V
-10V
RN (v)
500mV
10V
-10V
-500mV
10V
-10V
RN (h)
500mV
10V
-10V
-500mV
10V
-10V
DN
500mV
10V
-10V
-500mV
10V
-10V
DDN
500mV
10V
-10V
-500mV
10V
-10V
DDN0
500mV
10V
-10V
-500mV
10V
-10V
DDN1
500mV
10V
-10V
-500mV
10V
-10V
PN
500mV
10V
-10V
-500mV
10V
-10V
PN (v)
500mV
10V
-10V
-500mV
10V
-10V
PN (h)
500mV
10V
-10V
-500mV
10V
-10V
NPN
500mV
10V
-10V
-500mV
10V
-10V
TN@BER
500mV
10V
-10V
-500mV
10V
-10V
Unit
Amplitude
500mV
10V
-10V
-500mV
10V
-10V
Time Measurements
Rise Time
200 ns
1 ks
0s
0s
1 ks
0s
Setup
10 ns
1s
–1 s
0s
1s
–1 s
High Time
10 ns
1 Ms
1 ps
0s
1 Ms
1 ps
Fall Time
200 ns
1 ks
0s
0s
1 ks
0s
DPOJET Printable Application Help
243
Reference
Name
Measurement range limits (Max)
Measurement range limits (Min)
Default
Max
Min
Default
Max
Min
Rise Slew
Rate
1 V/ns
100 V/ns
1 uV/ns
0 V/ns
100 V/ns
0 V/ns
Fall Slew
Rate
0 V/ns
0 V/ns
–100 V/ns
–1 V/ns
–1 uV/ns
–100 V/ns
Hold
10 ns
1s
–1 s
0s
1s
–1 s
Low Time
10 ns
1 Ms
1 ps
1 ps
1 Ms
1 ps
Skew
10 ns
1s
–1 s
–10 ns
1s
–1 s
SSC Profile 1 ms
1 ks
0s
0s
1 ks
0s
SSC Mod
Rate
10 kHz
50 GHz
100 Hz
1 kHz
50 GHz
100 Hz
SSC Freq
Dev
1 kppm
1 Gppm
-1 Gppm
-1 kppm
1 Gppm
-1 Gppm
SSC Freq
Dev Min
1 kppm
1 Gppm
-1 Gppm
-1 kppm
1 Gppm
-1 Gppm
SSC Freq
Dev Max
1 kppm
1 Gppm
-1 Gppm
-1 kppm
1 Gppm
-1 Gppm
Time
Outside
Level
1 ms
1 ks
0s
0s
1 ks
0s
tCMD-CMD 1 ms
1 ks
0s
0s
1 ks
0s
500 mV
1 kV
0V
50 mV
1 kV
0V
Height@BE 500 mV
R
1 kV
0V
50 mV
1 kV
0V
Width
1 ns
1s
0s
50 ps
1s
0s
Mask Hits
500 Hits
1 MHits
0 Hits
0 Hits
1 MHits
0 Hits
Autofit Mask 500 Hits
Hits
1 MHits
0 Hits
0 Hits
1 MHits
0 Hits
Width@BER 0.9 UI
1.0 UI
0 UI
0.1 UI
1.0 UI
0 UI
Eye High
500 mV
10 V
-10 V
-500 mV
10 V
-10 V
Eye Low
500 mV
10 V
-10 V
-500 mV
10 V
-10 V
Q-Factor
1k
1G
0
0
1G
0
DC Common 500 mV
Mode
10 V
–10 V
–500 mV
10 V
–10 V
AC Common 500 mV
Mode
10 V
–10 V
–500 mV
10 V
–10 V
High
500 mV
10 V
–10 V
–500 mV
10 V
–10 V
T/nt-Ratio
8 dB
12 dB
–12 dB
0 dB
12 dB
–12 dB
High–Low
500 mV
10 V
–10 V
–500 mV
10 V
–10 V
Low
500 mV
10 V
–10 V
–500 mV
10 V
–10 V
Eye Measurements
Height
Amplitude Measurements
244
DPOJET Printable Application Help
Reference
Name
Measurement range limits (Max)
Measurement range limits (Min)
Default
Max
Min
Default
Max
Min
V–Diff–Xovr 500 mV
10 V
–10 V
–500 mV
10 V
–10 V
Overshoot
500 mV
10 V
0V
0 mV
10 V
0V
Undershoot 500 mV
10 V
0V
0V
10 V
0V
Cycle Pk-Pk 500 mV
10 V
-10 V
–500 mV
10 V
–10 V
Cycle Min
500 mV
10 V
-10 V
–500 mV
10 V
–10 V
Cycle Max
500 mV
10 V
-10 V
–500 mV
10 V
–10 V
Standard-Specific Measurements
DDR Setup– 10 ns
SE
1s
–1 s
0 ns
1s
–1 s
DDR Setup– 10 ns
Diff
1s
–1 s
0 ns
1s
–1 s
DDR Hold–
SE
10 ns
1s
–1 s
0 ns
1s
–1 s
DDR Hold–
Diff
10 ns
1s
–1 s
0 ns
1s
–1 s
DDR
tCK(avg)
1 ms
1 ks
0 ns
0 ns
1 ks
0 ns
DDR
tCH(avg)
1 ms
1 ks
0 ns
0 ns
1 ks
0 ns
DDR
tCL(avg)
1 ms
1 ks
0 ns
0 ns
1 ks
0 ns
DDR
tJIT(duty)
10 ns
1 ms
–1ms
–10 ns
1 ms
–1 ms
DDR
tJIT(per)
10 ns
1 ms
–1 ms
–10 ns
1 ms
–1 ms
DDR
tERR(n)
10 ns
1 ms
–1 ms
–10 ns
1 ms
–1 ms
DDR
tERR(m-n)
10 ns
1 ms
–1 ms
–10 ns
1 ms
–1 ms
DDR tRPRE 2.5 ns
1 ks
0s
0s
1 ks
0s
DDR tWPRE 2.5 ns
1 ks
0s
0s
1 ks
0s
DDR tPST
2.5 ns
1 ks
0s
0s
1 ks
0s
DDR Over
Area
660 mVs
1 kVs
0 Vs
0 Vs
1 kVs
0 Vs
DDR
UnderArea
660 mVs
1 kVs
0 Vs
0 Vs
1 kVs
0 Vs
DDR VID(ac) 500 mV
10 V
–10 V
–500 mV
10 V
–10 V
DDR tDQSS 1 ms
1 ks
0s
0s
1 ks
0s
DDR2
tCKSRE
1 ks
0s
0s
1 ks
0s
DPOJET Printable Application Help
1 ms
245
Reference
Name
5
246
Measurement range limits (Max)
Measurement range limits (Min)
Default
Max
Min
Default
Max
Min
DDR3 Vix(ac 500 mV
)
10 V
–10 V
–500 mV
10 V
–10 V
PCIe MedMx-Jitter
1 ms
1 ks
0s
0s
1 ks
0s
GDDR5
tCKSRX
1 ms
1 ks
0s
0s
1 ks
0s
GDDR5
0s
tBurst-CMD
0s
-100 s
-1 s
-1 μs
-100 s
GDDR5
tDQSCK
1 ms
1 ks
-1 ks
-1 ms
1 ks
0s
PCIe AC
Common
Mode
500 mV
10 V
–10 V
–500 mV
10 V
–10 V
PCIe T-RF- 1 ns
Mismch
1 ks
0s
0s
1 ks
0s
PCIe MAX- 1 V
MIN Ratio 5
10 V
–10 V
–1 V
10 V
–10 V
PCIe SSC 200 ns
FREQ DEV
1 ks
0s
0s
1 ks
0s
PCIe SSC
PROFILE
1 ms
1 ks
0s
0s
1 ks
0s
PCIe-T-TxDiff-PP
1V
10 V
–10 V
–1 V
10 V
–10 V
PCIe T-TX
1 ns
1s
0s
50 ps
1s
0s
PCIe T-TxFall
200 ns
1 ks
0s
0s
1 ks
0s
PCIe TminPulse
1 ms
1 ks
0s
0s
1 ks
0s
PCIe
DeEmph
8 dB
12 dB
–12 dB
0 dB
12 dB
–12 dB
PCIe T-TxRise
200 ns
1 ks
0s
0s
1 ks
0s
PCIe UI
1 ms
1 ks
0s
0s
1 ks
0s
T-TX-DDJ
1 ns
1 μs
0s
0s
1 μs
0s
T-TX-UTJ
1 ns
1 μs
0s
0s
1 μs
0s
T-TXUDJDD
1 ns
1 μs
0s
0s
1 μs
0s
T-TX-UPW- 1 ns
TJ
1 μs
0s
0s
1 μs
0s
Custom name for PCIe MAX-MIN Ratio is PCIe VRX-MAX-MIN Ratio.
DPOJET Printable Application Help
Reference
Name
Measurement range limits (Max)
Measurement range limits (Min)
Default
Max
Min
Default
Max
Min
T-TX-UPW- 1 ns
DJDD
1 μs
0s
0s
1 μs
0s
V-TX NO-EQ 1.2 V
2V
0V
0V
2V
0V
V-TX EIEOS 1.2 V
2V
0V
0V
2V
0V
ps21TX
8 dB
12 dB
–12 dB
0 dB
12 dB
–12 dB
V-TXBOOST
8 dB
12 dB
–12 dB
0 dB
12 dB
–12 dB
USB AC
Common
Mode
500 mV
10 V
–10 V
–500 mV
10 V
–10 V
USB VTxDiff-PP
1V
10 V
–10 V
–1 V
10 V
–10 V
USB TCdrSlew-Max
200 ns
1 ks
0s
0s
1 ks
0s
USB TminPulse-Tj
1 ms
1 ks
0s
0s
1 ks
0s
USB TminPulse-Dj
200 ns
1 ks
0s
0s
1 ks
0s
USB SSC
200 ns
MOD RATE
1 ks
0s
0s
1 ks
0s
USB SSC
200 ns
FREQ DEV
MAX
1 ks
0s
0s
1 ks
0s
USB SSC
200 ns
FREQ DEV
MIN
1 ks
0s
0s
1 ks
0s
USB SSC
PROFILE
1 ms
1 ks
0s
0s
1 ks
0s
USB UI
1 ms
1 ks
0s
0s
1 ks
0s
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Reference
Measurement units
The following table lists the engineering multipliers that the DPOJET application
uses.
Table 77: Measurement units
248
Abbreviation
Unit
Multiplier
y
yocto or septillionths
1E-24)
z
zepto or sextillionths
1E-21)
a
atto or quintillionths
1E-18)
f
femto or quadrillionths
1E-15)
p
pico or trillionths
1E-12)
n
nano or billionths
1E-09)
u
micro or millionths
1E-06)
m
milli or thousandths
1E-03)
one
1E+00)
k
kilo or thousands
1E+03)
M
mega or millions
1E+06)
G
giga or billions
1E+09)
T
tera or trillions
1E+12)
P
peta or quadrillions
1E+15)
E
exa or quintillions
1E+18)
Z
zetta or sextillions
1E+21)
Y
yotta or septillions
1E+24)
DPOJET Printable Application Help
Reference
Custom mask file requirements
DPOJET uses mask definition files that are compatible with TekScope firmware
user masks, and consist of ASCII text but are identified with a .msk file
extension. Any firmware mask can be saved as a user mask and imported into
DPOJET. Alternatively, DPOJET mask files can be manually created using an
ASCII text editor such as Notepad, or copied from an existing mask and then
edited. DPOJET doesn't require most of the fields found in a TekScope mask file,
so the minimum DPOJET mask file is substantially simpler.
The following fields are required:
:MASK:USER:SEG1:POINTS x1,y1,x2,y2,x3,y3,x4,y4;
:MASK:USER:SEG2:POINTS x1,y1,x2,y2,x3,y3,x4,y4;
:MASK:USER:SEG3:POINTS x1,y1,x2,y2,x3,y3,x4,y4;
Seg1 represents the top mask segment, typically used to detect overshoot.
Similarly, Seg3 is the base mask segment that detects undershoot. Seg2 is the
center-of-eye mask, which typically has four or six vertices. The mask vertices
are represented by xy pairs where x is in seconds and y is in volts. All mask
segments must be convex. The center of the eye is the time reference point t = 0.
For reasons beyond the scope of this document, it is not valid to have ALL time
values for ALL segments greater than zero.
The top and base segments can affect the eye diagram scale. The eye diagram
will always be scaled such that these segments are fully displayed.
If it is desired to disable a mask segment, use four identical vertices (conceptually
describing a rectangle with zero width and zero height). Such a segment will
cause no mask hits, although it can still affect eye diagram scaling. For
example, :MASK:USER:SEG1:POINTS 0,4,0,4,0,4,0,4; would disable the upper
segment, but it would force the top edge of the eye diagram to at least +4 V.
All other fields are optional, at the time of this writing, and are ignored by
DPOJET. It is possible that future versions of DPOJET software will use
additional fields as new features are added to TekScope firmware or DPOJET.
An example mask file is as follows. Only the last three lines are mandatory:
:MASK:USER:WID 400.0000E-12;
:MASK:USER:LAB "User Mask";
:MASK:USER:VSCA 200.0000E-3;
:MASK:USER:BITR 2.5000E+9;
:MASK:USER:SEG1:POINTS
-200.0000E-12,600.0000E-3,200.0000E-12,600.0000E-3,200.0000E12,800.0000E-3,-200.0000E-12,800.0000E-3;
:MASK:USER:SEG2:POINTS
-140.0000E-12,0.0000,25.8494E-27,-400.0000E-3,140.0000E12,0.0000,25.8494E-27,400.0000E-3;
DPOJET Printable Application Help
249
Reference
:MASK:USER:SEG3:POINTS
-200.0000E-12,-800.0000E-3,200.0000E-12,-800.0000E-3,200.0000E-12,600.0000E-3,-200.0000E-12,-600.0000E-3;
Correlation of measurement to configuration
The following tables list the configure tabs displayed for each measurement.
Table 78: Period/Freq measurements
UI Name Measure Edges
ments
Period
Bit
Config
Clock
RJDJ
Recover
y
Filters
General Global
Clock
RjDj
Recover
y
Filters
General Global
Clock
Period
Data
Period
Freq
Clock
Frequenc
y
Data
Frequenc
y
Pos
Width
Pos
Width
Neg
Width
Neg
Width
N–Period N–Period
+Duty
Cycle
+Duty
Cycle
-Duty
Cycle
-Duty
Cycle
CCPeriod
CCPeriod
+CC-Duty +CC-Duty
-CC-Duty -CC-Duty
Table 79: Jitter measurements
UI Name Measure Bit
ments
Config
TIE
Edges
Clock TIE
Data TIE
250
DPOJET Printable Application Help
Reference
UI Name Measure Bit
ments
Config
Edges
Clock
RjDj
Recover
y
Filters
General Global
TJ@BER Clock TJ
Data TJ
DCD
Clock
DCD
Data
DCD
RJ
Clock RJ
Data RJ
RJ (h)
RJ(v)
PJ(h)
PJ(v)
DJ
Clock DJ
Data DJ
DDJ
DDJ
RJ–δδ
Clock
RJ–δδ
Data RJ–
δδ
DJ–δδ
Clock
DJ–δδ
Data DJ–
δδ
PJ
Clock PJ
Data PJ
SRj
SRj
F/N
F/N
Jitter
Summary
1
Phase
Noise
J2
Clock TJ
Data TJ
J9
Clock TJ
Data TJ
1
Jitter Summary is not an individual measurement but a convenience function. Pressing this button
automatically adds a set of eleven jitter-related measurements with a single action. The measurements are: TIE,
RJ, RJ–δδ, DJ, DJ–δδ, PJ, DDJ, DCD, TJ@BER, and Width@BER.
DPOJET Printable Application Help
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Reference
Table 80: Noise measurements
UI Name
Measurem Bit config RnDn
ents
Clock
recovery
Filters
General
Global
RN
RN (v)
RN (n)
DN
DDN
DDN1
DDN0
PN
PN(v)
PN(h)
NPN
TN@BER
Unit
Amplitude
Noise
summary
2
Table 81: Timing measurements
Measure SSC
ments
Bus
State
Edges
Clock
RJDJ
Recover
y
Filters
General Global
Rise
Time
Fall Time
Skew
High
Time
Low Time
Setup
Rise Slew
Rate
Fall Slew
Rate
Hold
2
252
Noise Summary is not an individual measurement but a convenience function. Pressing this button
automatically adds a set of eleven noise-related measurements with a single action. The measurements are: RN,
DN, PN, DDN, DDN1, DDN0, TN@BER.
DPOJET Printable Application Help
Reference
Measure SSC
ments
Bus
State
Edges
Clock
RJDJ
Recover
y
Filters
General Global
Filters
General Global
SSC
Profile
SSC Mod
Rate
SSC Freq
Dev
SSC Freq
Dev Min
SSC Freq
Dev Max
Time
Outside
Level
tCMDCMD
Table 82: Eye measurements
Measure Bit
ments
Config
Edges
Clock
RNDN
Recover
y
RJDJ
Width
Width@B
ER
Height
Height@
BER
Mask Hits
Eye High
Eye Low
Q-Factor
AutoFit
Mask Hits
Table 83: Amplitude measurements
Measurem Bit Config Edges
ents
Clock
RJDJ
Recovery
Filters
General
Global
High
DC
Common
Mode
DPOJET Printable Application Help
253
Reference
Measurem Bit Config Edges
ents
Clock
RJDJ
Recovery
Filters
General
Global
AC
Common
Mode
Low
T/nT Ratio
High–Low
V–Diff–
Xovr
Overshoot
Undershoo
t
Cycle PkPk
Cycle Min
Cycle Max
Table 84: Standard-specific measurements
Measure Bus
ments
State
Bit
Config
Edges
Clock
BER
Recover
y
Filters
General Global
DDR
DDR
Setup-SE
DDR
Setup-Diff
DDR
Hold-SE
DDR
Hold-Diff
DDR
tCK(avg)
DDR
tCH(avg)
DDR
tCL(avg)
DDR
tERR(n)
DDR
tERR(mn)
DDR
tJIT(duty)
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DPOJET Printable Application Help
Reference
Measure Bus
ments
State
Bit
Config
Edges
Clock
BER
Recover
y
Filters
General Global
DDR
tJIT(per)
DDR
tRPRE
DDR
tWPRE
DDR
tPST
DDR
Over
Area
DDR
Under
Area
DDR
tDQSS
DDR
VID(ac)
GDDR5
tBurstCMD
GDDR5
tCKSRE
GDDR5
tCKSRX
DDR2
tDQSCK
PCI Express
PCIe
Med-MxJitter
PCIe TRFMismch
PCIe
MAX-MIN
Ratio 3
PCIe
SSC
FREQ
DEV
3
Custom name for PCIe MAX-MIN Ratio is PCIe VRX-MAX-MIN Ratio.
DPOJET Printable Application Help
255
Reference
Measure Bus
ments
State
Bit
Config
Edges
Clock
BER
Recover
y
Filters
General Global
PCIe
SSC
PROFILE
PCIe TTx-DiffPP
PCIe TTX
PCIe TTx-Fall
PCIe
TminPulse
PCIe
DeEmph
PCIe TTx-Rise
PCIe UI
PCIe AC
Common
Mode
T-TX-DJ
T-TX-UTJ
T-TXUDJDD
T-TXUPW-TJ
T-TXUPWDJD
D
V-TX-NOEQ
V-TXEIEOS
ps21TX
USB 3.0 Essentials
USB VTxDiff-PP
USB
TCdrSlew-Max
256
DPOJET Printable Application Help
Reference
Measure Bus
ments
State
Bit
Config
Edges
Clock
BER
Recover
y
Filters
General Global
USB
TminPulse-Tj
USB
TminPulse-Dj
USB SSC
MOD
RATE
USB SSC
FREQDEV
MAX
USB SSC
FREQ
DEV-MIN
USB SSC
PROFILE
USB UI
USB AC
Common
Mode
DPOJET Printable Application Help
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Reference
258
DPOJET Printable Application Help
Algorithms
About algorithms
The DPOJET application can take measurements from one or two waveforms.
The number of waveforms used by the application depends on the type of
measurement being taken.
Oscilloscope setup
guidelines
For all measurements, use the following guidelines to set up the oscilloscope:
1. The signal is any channel, reference, or math waveform.
2. The vertical scale for the waveform must be set so that the waveform does
not exceed the vertical range of the oscilloscope.
3. The sample rate must be set to capture sufficient waveform detail and avoid
aliasing.
4. Longer record lengths increase measurement accuracy but the oscilloscope
takes longer to measure each waveform.
Period/Freq measurements
Period
If the Signal Type is Clock. The Period measurement calculates the duration of a
cycle as defined by a start and a stop edge. Edges are defined by polarity,
threshold, and hysteresis. The application calculates clock period measurement
using the following equation:
Where:
PClock is the clock period.
T is the VRefMid crossing time for the selected polarity.
DPOJET Printable Application Help
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Algorithms
If the Signal Type is Data. The Period measurement calculates the duration of a
Unit Interval. The application calculates this measurement using the following
equation:
Where:
PData is the data period.
TData is the VRefMid crossing time in either direction.
Kn = Cn–Cn-1 is the estimated number of unit intervals between two successive
edges. Cn is the calculated data bit index of TnData.
Each measurement result PnData is repeated Kn times in the measurement result
vector, so that the measurement population is equal to the number of unit
intervals in the qualified waveform, rather than the number of edge pairs.
Positive and negative
width
Amount of time the waveform remains above/below the mid reference voltage
level.
The application calculates these measurements using the following equations:
Where:
W+ is the positive pulse width.
W— is the negative pulse width.
T— is the VRefMid crossing on the falling edge.
T+ is the VRefMid crossing on the rising edge.
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DPOJET Printable Application Help
Algorithms
Frequency
Frequency measurement calculates the inverse of the data period for each cycle.
If the Signal Type is Clock. The application calculates clock frequency
measurement using the following equation:
Where:
FClock is the clock frequency.
PClock is the clock period measurement.
If the Signal Type is Data. The application calculates data frequency measurement
using the following equation:
Where:
FData is the data frequency.
PData is the data period measurement.
N-Period
If the Signal Type is Clock. The N–Period measurement calculates the elapsed time
for N consecutive crossings of the mid reference voltage level in the direction
specified.
The application calculates this measurement using the following equation:
Where:
NPClock is the accumulated period for N clock cycles.
TClock is the VRefMid crossing time for the selected edge polarity.
DPOJET Printable Application Help
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Algorithms
If the Signal Type is Data. The N–Period measurement calculates the elapsed time
for N consecutive unit intervals.
The application calculates this measurement using the following equation:
Where:
NPData is the duration for N unit intervals.
TData is the VRefMid crossing time in either direction.
If Tn+NData does not exist for a given n, no measurement is recorded for that
position.
Positive and negative duty
cycle
The +Duty Cycle and –Duty Cycle measurements calculate the ratio of the
positive (or negative) portion of the cycle relative to the period.
The application calculates these measurements using the following equations:
Where:
D+ is the positive duty cycle.
D— is the negative duty cycle.
W+ is the positive pulse width.
W— is the negative pulse width.
PClock is the period.
Related topics.
Period
Positive and negative width
262
DPOJET Printable Application Help
Algorithms
CC-Period
The CC–Period measurement calculates the difference in period measurements
from one cycle to the next.
The application calculates CC–Period measurement using the following equation:
Where:
ΔP is the difference between adjacent periods.
PClock is the clock period measurement.
Positive and negative CC
duty
The + CC–Duty and – CC–Duty measurements calculate the difference in
positive (or negative) pulse widths from one cycle to the next.
The application calculates these measurements using the following equations:
Where:
ΔW+ is the difference between positive pulse widths of adjacent clock cycles.
ΔW— is the difference between negative pulse widths of adjacent clock cycles.
W+ is the positive pulse width measurement.
W— is the negative pulse width measurement.
DPOJET Printable Application Help
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Algorithms
Jitter measurements
TIE
TIE (Time Interval Error) is the difference in time between an edge in the source
waveform and the corresponding edge in a reference clock. The reference clock is
usually determined by a clock recovery process performed on the source
waveform. For Explicit-Clock clock recovery, the process is performed on an
explicitly identified source.
If the Signal Type is Clock. The application calculates Clock TIE measurement
using the following equation:
Where:
TIEClock is the clock time interval error.
TClock is the VRefMid crossing time for the specified clock edge.
T'Clock is the corresponding edge time for the specified reference clock.
If the Signal Type is Data. The application calculates Data TIE measurement using
the following equation:
Where:
TIEData is the data time interval error.
TData is the VRefMid crossing time in either direction.
T'Data is the corresponding edge time for the specified reference clock.
The subscript k is used to indicate that there is one measurement per Unit
Interval, rather than one measurement per actual edge.
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DPOJET Printable Application Help
Algorithms
RJ
Random Jitter (RJ) is the rms magnitude of all timing errors not exhibiting
deterministic behavior. A single RJ value is determined for each acquisition, by
means of RJ-DJ separation analysis.
Related topics.
Jitter analysis through RJ-DJ separation
RJ(h)
RJ(h) is the portion of RJ attributable to random horizontal displacement of the
localized waveform. Compare this to RJ(v). Since RJ(h) and RJ(v) are
uncorrelated, RJ = sqrt(RJ(h)2 + RJ(v)2).
Related topics. Joint Jitter/Noise Analysis
Noise model component interrelationships
RJ(v)
RJ(v) is the portion of RJ attributable to random vertical noise. If the waveform
slew rate is infinite at each transition, noise would have no effect on the edge
timing. Since the waveform slew rate is finite on each transition, some amount of
noise is manifested as jitter. Since RJ(h) and RJ(v) are uncorrelated, RJ =
sqrt(RJ(h)2 + RJ(v)2).
Related topics. Joint Jitter/Noise Analysis
Noise model component interrelationships
Dual dirac random jitter
Dual Dirac Random Jitter (RJ–δδ) is the rms magnitude of all timing errors not
exhibiting deterministic behavior, calculated based on a simplifying assumption
that the histogram of all deterministic jitter can modeled as a pair of equalmagnitude dirac functions (impulses). A single RJ–δδ value is determined for
each acquisition, by means of RJ-DJ separation analysis.
Related topics.
Jitter analysis through RJ-DJ separation
Jitter estimation using Dual-Dirac models
DPOJET Printable Application Help
265
Algorithms
Jitter summary
TJ@BER
The Jitter Summary is not a single measurement. The Jitter Summary button on
the graphical user interface simply creates one each of all the other jitter
measurements, as a convenience. This convenience function is not supported via
the programmable interface.
Total Jitter at a specified Bit Error Rate (BER). This extrapolated value predicts a
peak-to-peak jitter that will only be exceeded with a probability equal to the
BER. It is generally not equal to the total jitter actually observed in any given
acquisition. A single TJ@BER value is determined for each acquisition, by
means of RJ-DJ separation analysis.
Related topics.
Jitter analysis through RJ-DJ separation
Estimation of TJBER and eye WidthBER
DJ
Deterministic Jitter (DJ) is the peak-to-peak amplitude for all timing errors that
follow deterministic behavior. A single DJ value is determined for each
acquisition, by means of RJ-DJ separation analysis.
Related topics.
Jitter analysis through RJ-DJ separation
Dual dirac deterministic
jitter
Dual Dirac Deterministic Jitter (DJ–δδ) the peak-to-peak magnitude for all timing
errors exhibiting deterministic behavior, calculated based on a simplifying
assumption that the histogram of all deterministic jitter can modeled as a pair of
equal magnitude dirac functions (impulses). A single DJ–δδ value is determined
for each acquisition, by means of RJ-DJseparation analysis.
Related topics.
Jitter analysis through RJ-DJ separation
Jitter estimation using Dual-Dirac models
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Phase noise
The Phase Noise measurement performs a jitter measurement, converts the result
into the frequency domain, and reports the rms jitter integrated between two
specific frequencies selected by the user.
The phase noise measurement is defined only for clock signals. If the source
waveform appears to be a data signal, a warning message will be produced but
the measurement will proceed.
A Phase Noise measurement is required in order to enable the Phase Noise plot.
PJ
Periodic Jitter (PJ) is the peak-to-peak amplitude for that portion of the
deterministic jitter which is periodic, but for which the period is not correlated
with any data pattern in the waveform. A single PJ value is determined for each
acquisition, by means of RJ-DJ separation analysis.
Related topics.
Jitter analysis through RJ-DJ separation
PJ(h)
PJ(h) is the portion of PJ attributable to periodic horizontal displacement of the
waveform. Compare this to PJ(v). For any given frequency, PJ(h) and PJ(v) are
correlated and added algebraically. If PJ(h) and PJ(v) are at the same frequency
but of opposite phase, one or both can be larger than PJ.
Related topics. Joint Jitter/Noise Analysis
Noise model component interrelationships
PJ(v)
PJ(v) is the portion of PJ attributable to periodic vertical noise. If the waveform
slew rate is infinite at each transition, noise would have no effect on the edge
timing. Since the waveform slew rate is finite on each transition, some amount of
noise is manifested as jitter. For any given frequency, PJ(h) and PJ(v) are
correlated and added algebraically. If PJ(h) and PJ(v) are at the same frequency
but of opposite phase, one or both can be larger than PJ.
Related topics. Joint Jitter/Noise Analysis
Noise model component interrelationships
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NPJ
Non-Periodic Jitter (NPJ) is the dual-dirac magnitude of that portion of Bounded
Uncorrelated Jitter (BUJ) that is not periodic. Since it is not periodic and is not
correlated with the data pattern, NPJ is frequently difficult to distinguish from
(Gaussian) RJ.
This component of jitter is not analyzed by default, but you can enable it by
switching the jitter analysis mode to Spectral + BUJ. Since it typically requires
high populations to distinguish, you may need to acquire multiple waveforms
before jitter results are available when Spectral + BUJ mode is enabled.
Related topics.
Separation of Non-Periodic jitter (NPJ)
Preferences jitter decomp
DDJ
Data-Dependent Jitter (DDJ) is the peak-to-peak amplitude for that portion of the
deterministic jitter directly correlated with the data pattern in the waveform. A
single DDJ value is determined for each acquisition, by means of RJ-DJ
separation analysis.
Related topics.
Jitter analysis through RJ-DJ separation
DCD
Duty Cycle Distortion (DCD) is the peak-to-peak amplitude for that portion of
the deterministic jitter directly correlated with signal polarity, that is the
difference between the mean positive edge displacement versus that on negative
edges. A single DCD value is determined for each acquisition, by means of RJDJ separation analysis.
Related topics.
Jitter analysis through RJ-DJ separation
J2
J2 is Total Jitter at a Bit Error Rate (BER) value of 2.5E-3. This statistical value
predicts a peak-to-peak jitter that will only be exceeded with a probability equal
to the BER.
Related topics.
Jitter analysis through RJ-DJ separation
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J9
J9 is Total Jitter at a Bit Error Rate (BER) value of 2.5E-10. This statistical value
predicts a peak-to-peak jitter that will only be exceeded with a probability equal
to the BER.
Related topics.
Jitter analysis through RJ-DJ separation
SRJ
Sub-Rate Jitter is periodic jitter at a rate that integrally divides the data rate. For
example, if the data rate is F bits/second, sub-rate jitter components could occur
at F/2 or F/4. It typically occurs when a serial data stream is formed by
multiplexing (interleaving) an integral number of lower-rate bit streams together,
although there can be other causes. Sub-rate jitter is a sub-component of PJ.
The SRJ measurement is the peak-to-peak amplitude for the sum of all F/N jitter
components that are tracked by DPOJET. Since different F/N components are
correlated with each other, the peak-to-peak SRJ depends on relative phases and
is not simply the sum of the individual F/N components.
The SRJ measurement always tracks and accounts for N = 2, 4 and 8 regardless
of whether the corresponding F/N measurements have been selected.
Related topics.
F/N
Jitter analysis through RJ-DJ separation
F/N
Conceptually, F/N jitter is the peak-to-peak amplitude of periodic jitter occurring
at a rate that divides the data rate (F) by the integer N. However, it excludes jitter
occurring at harmonics of F/N. For example, F/4 jitter occurs at one fourth the
data rate (but the measurement excludes jitter attributable to F/2 before
determining the peak-to-peak amplitude).
For a repeating data pattern, some deterministic jitter can be interpreted either as
DDJ or as F/N jitter. This condition occurs when the pattern length, P, is an
integer multiple of N. By convention, such jitter is reported as DDJ, and the
corresponding F/N is reported as zero. For example, a signal with a pattern length
of 10 would report F/2 = 0 since jitter at half the bit rate can be interpreted as
DDJ. But F/4 and F/8 may be non-zero since they cannot be DDJ for this pattern
length.
The measurement uses a divisor (N) of 2 by default but a divisor of 2, 4 or 8 can
be selected.
For a given N, the value of F/N is computed as follows:
For a data stream of I bits, the mean jitter for each of the phases n ∈{1, 2, … N}
is calculated as:
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The jitter-per-phase is collected into a jitter trend or array:
From this trend, the trends attributable to higher harmonics are removed (for
example, the T2 and T4 trends are subtracted from the T8 trend):
The peak-to-peak jitter is then:
From this trend, the trends attributable to higher harmonics are removed (for
example, the T2 and T4 trends are subtracted from the T8 trend):
For a repeating data pattern with repeat length N, some deterministic jitter falls in
an ambiguous category where it could be interpreted either as DDJ or as F/N
jitter. By convention, such jitter is reported as DDJ, and the corresponding F/N is
reported as zero.
Related topics.
SRJ
Jitter analysis through RJ-DJ separation
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Noise measurements
TN@BER
Total Noise at a specified Bit Error Rate (BER). This extrapolated value predicts
a peak-to-peak vertical eye closure (relative to the estimated bit amplitude) that
will only be exceeded with a probability equal to the BER. It is generally not
equal to the total vertical closure actually observed in any given acquisition. A
single TN@BER value is determined for each acquisition, by means of RN-DN
separation analysis.
Related topics. Joint Jitter/Noise analysis
Noise model component interrelationships
RN
Random Noise (RN) is the rms magnitude of all vertical deviations from nominal
bit amplitude not exhibiting deterministic behavior. A single RN value is
determined for each acquisition, by means of RN-DN separation analysis.
Related topics. Joint Jitter/Noise analysis
Noise model component interrelationships
RN(v)
RN(v) is the portion of RN attributable to random vertical displacement of the
waveform. Compare this to RN(h). Since RN(v) and RN(h) are uncorrelated, RN
= sqrt(RN(v)2 + RN(h)2).
Related topics. Joint Jitter/Noise Analysis
Noise model component interrelationships
RN(h)
RN(h) is the portion of RN attributable to random jitter. If the waveform slew
rate is zero across the center of each bit, jitter will have no effect on vertical
measurements at this point. But if the waveform slew rate is not zero at the center
of each bit, some amount of jitter is manifested as vertical displacement. Since
RN(v) and RN(h) are uncorrelated, RN = sqrt(RN(v)2 + RN(h)2).
Related topics. Joint Jitter/Noise Analysis
Noise model component interrelationships
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DN
Deterministic Noise (DN) is the peak-to-peak amplitude for all vertical deviations
from nominal bit amplitude that follow deterministic behavior. A single DN
value is determined for each acquisition, by means of RN-DN separation
analysis.
Related topics. Joint Jitter/Noise analysis
Noise model component interrelationships
PN
Periodic Noise (PN) is the peak-to-peak amplitude for that portion of the
deterministic noise which is periodic, but for which the period is not correlated
with any data pattern in the waveform. A single PN value is determined for each
acquisition, by means of RN-DN separation analysis.
Related topics. Joint Jitter/Noise analysis
Noise model component interrelationships
PN(v)
PN(v) is the portion of PN attributable to periodic vertical displacement of the
waveform. Compare this to PN(h). For any given frequency, PN(v) and PN(h) are
correlated and added algebraically. If PN(v) and PN(h) are at the same frequency
but of opposite phase, one or both can be larger than PN.
Related topics. Joint Jitter/Noise Analysis
Noise model component interrelationships
PN(h)
PN(h) is the portion of PN attributable to periodic jitter. If the waveform slew
rate is zero across the center of each bit, jitter will have no effect on vertical
measurements at this point. But if the waveform slew rate is not zero at the center
of each bit, some amount of jitter is manifested as vertical displacement. For any
given frequency, PN(v) and PN(h) are correlated and added algebraically. If
PN(v) and PN(h) are at the same frequency but of opposite phase, one or both can
be larger than PN.
Related topics. Joint Jitter/Noise Analysis
Noise model component interrelationships
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DDN(0)
Data-Dependent Noise for 0 bits (DDN(0)) is the peak-to-peak amplitude for all
bit pattern-correlated vertical variations of low bits from the nominal low level, at
the center of the eye. A single DDN(0) value is determined for each acquisition.
Related topics. Joint Jitter/Noise analysis
Noise model component interrelationships
DDN(1)
Data-Dependent Noise for 1 bits (DDN(1)) is the peak-to-peak amplitude for all
bit pattern-correlated vertical variations of high bits from the nominal high level,
at the center of the eye. A single DDN(1) value is determined for each
acquisition.
Related topics. Joint Jitter/Noise analysis
Noise model component interrelationships
DDN
Data-Dependent Noise (DDN) is the total vertical eye closure due to bit patterncorrelated vertical variations, at the center of the eye. It is the sum of the positive
peak DDN(0) relative to the nominal low level, and the negative peak DDN(1)
relative to the nominal high level. A single DDN value is determined for each
acquisition.
Related topics. Joint Jitter/Noise analysis
Noise model component interrelationships
NPN
Non-Periodic Noise (NPN) is the dual-dirac magnitude of that portion of
Bounded Uncorrelated Noise (BUN) that is not periodic. Since it is not periodic
and is not correlated with the data pattern, NPN is frequently difficult to
distinguish from (Gaussian) RN. This component of noise is not analyzed by
default, but you can enable it by switching the analysis mode to Spectral + BUJ.
Since it typically requires high populations to distinguish, you may need to
acquire multiple waveforms before noise results are available when Spectral +
BUJ mode is enabled.
Related topics. Separation of Non-Periodic jitter (NPJ)
Preferences-Jitter decomp
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Unit Amplitude
The Unit Amplitude is the automatically determined nominal eye amplitude at
the horizontal center of the eye. The nominal High level is the mean value of the
distribution that represents DDN(1), and the nominal Low level is the mean value
of the distribution that represents DDN(0). Unit Amplitude is the difference
between these nominal High and Low values, and it is used to normalize all the
other noise measurements if the units are switched from absolute to normalized.
The actual High and Low levels are not individually reported, but they are
depicted on plots such as the BER Eye Contour, PDF Eye, Correlated Eye, using
pink dots positioned along a vertical line at the eye center.
Related topics. Joint Jitter/Noise analysis
Noise model component interrelationships
Noise summary
The Noise Summary is not a measurement. The Noise Summary button on the
graphical user interface simply creates one each of all the primary noise
measurements, as a convenience. The function is also accessible via the
programmable interface.
Timing measurements
Rise time
The Rise Time measurement is the time difference between when the VRefHi
reference level is crossed and the VRefLo reference level is crossed on the rising
edge of the waveform. The Rise Time algorithm uses the VRef values as the
reference voltage level. Each edge is defined by the slope, voltage reference level
(threshold), and hysteresis.
The application calculates this measurement using the following equation:
Where:
T Rise is the Rise Time.
T Hi+ is the VRefHi crossing on the rising edge.
T Lo+ is the VRefLo crossing on the rising edge.
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Fall time
The Fall Time measurement is the time difference between when the VRefLo
reference level is crossed and the VRefHi reference level is crossed on the falling
edge of the waveform. The Fall Time algorithm uses the VRef values as the
reference voltage level. Each edge is defined by the slope, voltage reference level
(threshold), and hysteresis.
The application calculates this measurement using the following equation:
Where:
T Fall is the Fall Time.
T Lo- is the VRefLo crossing on the falling edge.
T Hi- is the VRefHi crossing on the falling edge.
Skew
The Skew measurement calculates the difference in time between the designated
edge on a principle waveform to the designated edge on another waveform. The
closest data edge to the clock edge that falls within the range limits is used.
The application calculates this measurement using the following equation:
Where:
T Skew is the timing skew.
T Main is the Main input VRefMidMain crossing time in the specified direction.
T 2nd is the 2nd input VRefMid2nd crossing time in the specified direction.
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High time
The High Time Measurement is the amount of time that a waveform cycle is
above the VRefHi voltage reference level.
The application calculates the measurement using the following equation:
Where:
T High is the high time.
T Hi- is the VRefHi crossing on the falling edge.
T Hi+ is the VRefHi crossing on the rising edge.
Low time
The Low Time measurement is the amount of time that a waveform cycle is
below the VRefLo voltage reference level.
The application calculates this measurement using the following equation:
Where:
T Low is the low time.
T Lo+ is the VRefLo crossing on the rising edge.
T Lo- is the VRefLo crossing on the falling edge.
Setup
The Setup Time measurement is the elapsed time between the designated edge of
a data waveform and when the clock waveform crosses its own voltage reference
level. The closest data edge to the clock edge that falls within the range limits is
used.
The application calculates this measurement using the following equation:
Where:
T Setup is the setup time.
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T Main is the Main input (clock) VRefMidMain crossing time in the specified
direction.
T 2nd is the 2nd input (data) VRefMid2nd crossing time in the specified
direction.
NOTE. The order of the input sources for Setup and Hold measurements (Source1
= Clock, Source2 = Data) differs from the order of input sources on the Setup/
Hold Trigger menu in the oscilloscope.
Rise slew rate
The Rise Slew Rate is defined as the rate of change of the voltage between the
crossings of the specified VREFHI and VREFLO reference voltage levels. The
voltage difference is measured between the VREFHI reference level crossing and
the VREFLO reference level crossing on the rising edge of the waveform. The time
difference is measured as the difference between the low time, and the low time
at which VREFLO and VREFHI are crossed. The Rise Slew Rate algorithm uses the
high and low rise reference voltage levels to configure the values. Each edge is
defined by the slope, voltage reference level (threshold), and the hysteresis.
The application calculates this measurement using the following equation:
Related topics.
High mid and low reference voltage levels
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Fall slew rate
The Fall Slew Rate is defined as the rate of change of the voltage at the specified
VREFLO and VREFHI reference voltage levels. The voltage difference is measured
between the VREFLO reference level crossing and the VREFHI reference level
crossing on the falling edge of the waveform. The time difference is measured as
the difference between the high time and low time at which VREFHI and VREFLO
are crossed. The Fall Slew Rate algorithm uses the low time and high fall
reference voltage levels to configure the values. Each edge is defined by the
slope, voltage reference level (threshold), and the hysteresis.
The application calculates this measurement using the following equation:
Related topics.
High mid and low reference voltage levels
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Hold
The Hold Time measurement is the elapsed time between when the clock
waveform crosses its own voltage reference level and the designated edge of a
data waveform. The closest data edge to the clock edge that falls within the range
limits is used.
The application calculates this measurement using the following equation:
Where:
THold is the hold time.
TMain is the Main input (clock) VRefMidMain crossing time in the specified
direction.
T2nd is the 2nd input (data) VRefMid2nd crossing time in the specified direction.
NOTE. The order of the input sources for Setup and Hold measurements (Source1
= Clock, Source2 = Data) differs from the order of input sources on the Setup/
Hold Trigger menu in the oscilloscope.
SSC profile
SSC Profile shows the modulation profile of the Spread Spectrum Clocking
(SSC). It is the time trend plot of the SSC profile. All SSC measurements use the
Period measurement with a second order low pass filter. Using the profile you
can analyze the SSC modulation rate by using the horizontal cursors. You can
also analyze the peak-to-peak frequency deviation by using the vertical cursors.
The following are the default configurations that are required:
■
Constant Clock Recovery (CCR) Mean set as the Clock Recovery method.
■
Low pass filter with 1.98 MHz cut off frequency set by default. This is the
standard FiberChannel cut off frequency.
■
Available plots are Time Trend, Data Array, Histogram and Spectrum plots.
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SSC MOD rate
SSC Mod Rate measurement computes the SSC modulating frequency.
The following are the default configurations that are required:
SSC FREQ DEV MIN
■
Constant Clock Recovery (CCR) Mean set as the Clock Recovery method.
■
Low pass filter with 1.98 MHz cut off frequency set by default. This is the
standard FiberChannel cut off frequency.
■
Available plots are Time Trend, Data Array, Histogram and Spectrum plots.
The SSC FREQ DEV MIN is defined as the minimum frequency shift as a
function of time. It represents the frequency deviation in terms of ppm (parts per
million).
■
Find the 50% edges on the SSC profile.
■
Calculate the LOW value between the n and n+1 edge.
■
Find the Minimum frequency deviation as LOW.
The application calculates the measurement using the equation:
Freq Dev Min(ppm)= ((Minimum Freq–Nominal Data Rate)/Nominal Data
Rate)* 1e6
Available plots are Time Trend, Data Array, Histogram and Spectrum plots.
SSC FREQ DEV MAX
SSC FREQ DEV MAX is defined as the maximum frequency shift as a function
of time. It represents the frequency deviation in terms of ppm (parts-per-million).
■
Find the 50% edges on the SSC profile
■
Calculate the HIGH value between the n and n+1 edge
■
Find the Maximum frequency deviation as HIGH
The application calculates the measurement using the equation:
Freq Dev Max(ppm)= ((Maximum Freq – Nominal Data Rate)/Nominal Data
Rate)* 1e6
The difference between the SSC FREQ DEV MAX and SSC FREQ DEV MIN
measurements are that they compute the maximum frequency deviation and
minimum frequency deviation separately. By doing this the limits can be applied
separately.
Available plots are Time Trend, Data Array, Histogram and Spectrum plots.
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SSC FREQ DEV
SSC FREQ DEV is defined as the SSC frequency deviation in ppm (parts per
million).
■
The low pass filter is turned on by default with 1.98 MHz as the cut off
frequency. This is set to the standard FiberChannel cut off frequency.
■
Time Trend, Data Array, Histogram, and Spectrum plots are allowed for this
measurement.
The application calculates the measurement using the equation:
FREQ DEVIATION = HIGH–LOW
Related topics.
High
Low
tCMD-CMD
Time outside level
tCMD-CMD measures the elapsed time between two bus states, for example
CMD_1 and CMD_2. For each state, the relevant timing point can be specified as
the start of the state, the end of the state, or a rising or falling edge on a
separately-specified clock source. The timing resolution of this measurement is
dependent on the sample clock used. For example, if the bus is composed of
digital channels sampled as 12.5 Gsps, the resolution is 80 ps.
Time Outside Level is defined as the time interval of overshoot or undershoot.
The measurement is taken on both the rising and falling slopes.
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Eye diagram measurements
Eye width
The Eye Width measurement is the measured minimum horizontal eye opening at
the zero reference level.
The application calculates this measurement using the following equation:
Where:
UIAVG is the average UI.
TIE pk-pk is the Peak-Peak TIE.
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Width@BER
Width@BER is the Eye Width at a specified Bit Error Rate (BER). This
extrapolated value predicts a horizontal eye opening that will be violated with a
probability equal to the BER. It is generally not equal to the eye width actually
observed in any given acquisition. A single Width@BER value is determined for
each acquisition, by means of RJ-DJ separation analysis.
Related topics.
Jitter analysis through RJ-DJ separation
Estimation of TJ@BER and eye Width@BER
Eye height
The Eye Height measurement is the measured minimum vertical eye opening at
the UI center as shown in the plot of the eye diagram. There are three types of
Eye Height values.
The application calculates this measurement using the following equation:
Where:
VEYE-HI-MIN is the minimum of the High voltage at mid UI.
TIEEYE-LO-MAX is the maximum of the Low voltage at mid UI.
Eye Height-Transition. The application calculates this measurement using the
following equation:
Where:
VEYE-HI-TRAN-MIN is the minimum of the High transition bit eye voltage at
mid UI.
TIEEYE-LO-TRAN-MAX is the maximum of the Low transition bit eye voltage at
mid UI.
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Eye Height-Non-Transition. The application calculates this measurement using the
following equation:
Where:
VEYE-HI-NTRAN-MIN is the minimum of the High non- transition bit eye
voltage at mid UI.
TIEEYE-LO-NTRAN-MAX is the maximum of the Low non-transition bit eye
voltage at mid UI.
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Height@BER
Height@BER is the Eye Height at a specified Bit Error Rate (BER). This
extrapolated value predicts a vertical eye opening that will be violated with a
probability equal to the BER. It is generally not equal to the eye height actually
observed in any given acquisition. A single Height@BER value, in the given
interval, is determined for each acquisition by means of Q-scale extrapolation.
Eye high
Eye High calculates the voltage at a selected horizontal position across the unit
interval, for all High bits in the waveform. You specify the offset at which the
measurement takes place from 0% to 100% of the unit interval. Configure the
measurement to include all bits, only transition bits, or only non-transition bits.
(Note that some of the waveform can be omitted from the measurement due to
initialization of clock recovery or filtering.) A histogram of the Eye High
measurement corresponds to a vertical slice through the upper half of a threedimensional eye diagram.
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Eye low
Eye Low calculates the voltage at the selected horizontal position across the unit
interval, for all Low bits in the waveform. A histogram of the Eye Low
measurement corresponds to a vertical slice through the lower half of a threedimensional eye diagram.
Q-factor
Quality Factor is the ratio of eye size to noise. Eye and Q factor measurements
can be run together and displayed onto a single window.
The final measurement value would be computed according to the equation
below:
Q-factor = [mean(EyeHigh) - mean(EyeLow)] / [stddev(EyeHigh) +
stddev(EyeLow)]
Where:
Eye High: the sample values of positive UI at x%.
Eye Low: the sample values of negative UI at x%.
For more details refer Eye Height
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Mask hits
The Mask hits measurement reports the number of unit intervals in the
acquisition for which mask hits occurred, for a user-specified mask. In the
Results Summary view, the Mask hits measurement reports the total number of
unit intervals for which a mask hit occurred in at least one mask zone. In the
Results Details view, the number of hits in each of three segments is reported.
The Mask hits measurement has several unique properties:
Autofit mask hits
■
Unlike other measurements, it requires a Mask hits plot. Adding a Mask hits
measurement will cause the corresponding plot to be created automatically. If
you delete a Mask hits plot, the application will remove the corresponding
Mask hits measurement after verifying the action with you.
■
The Mask hits measurement does not support the Worst-Case Waveforms
logging feature.
■
The Mask hits measurement does not support Measurement Range Limits.
■
The Mask hits measurement does not support Population Limit.
Autofit Mask hits measurement reports the number of pixels in the acquisition for
which mask hits occurred, for a user specified mask. In the results summary
view, Autofit Mask Hits measurement reports the total number of Pixel Hits for
which a mask hit occurred. In the Results Details View, the number of hits in
each of three segments is reported. The population field shows the total number
of unit intervals measured.
The AUTOFIT Mask Hits measurement has several unique properties:
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■
Unlike other measurements, it requires a Mask hits plot. Adding an Autofit
Mask Hits measurement will cause the corresponding plot to be created
automatically. If you delete a Mask Hits plot, the application will remove the
corresponding Autofit Mask Hits measurement after verifying the action with
you.
■
The Autofit Mask Hits measurement does not support Worst-Case
Waveforms logging.
■
The Autofit Mask Hits measurement does not support Measurement Range
Limits.
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Amplitude measurements
High
The High Amplitude measurement calculates the mean or mode of a selected
portion of each unit interval corresponding to a “1” bit.
The application calculates this measurement using the following equation:
Where:
VHI is the high amplitude measurement result.
OP[• ] is the selected Operation (either Mean or Mode).
vPERCENT is the set of voltage samples over the selected portion (percent) of
the unit interval, ranging from 1% to 100%.
n is the index of a high bit, a high transition bit, or a high non-transition bit.
Low
The Low Amplitude measurement calculates the mean or mode of a selected
portion of each unit interval corresponding to a “0” bit.
The application calculates this measurement using the following equation:
Where:
VLOW is the low amplitude measurement result.
OP[• ] is the selected Operation (either Mean or Mode).
vPERCENT is the set of voltage samples over the selected portion (percent) of
the unit interval, ranging from 1% to 100%.
n is the index of a low bit, a low transition bit, or a low non-transition bit.
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DC common mode
The Common Mode Voltage measurement (also called DC Common Mode)
calculates the mean of the Common Mode voltage waveform.
The application calculates this measurement using the following equation:
Where:
VCM is the common mode voltage measurement.
is the common mode voltage waveform.
i is the sample index of common mode waveform values.
AC common mode
The AC Common Mode Voltage measurement is the common mode voltage
between two single-ended signals. AC is defined as all the frequency components
above the cutoff frequency (30 kHz).
The application calculates this measurement using the following equations (based
on two single-ended sources from the DUT):
CM_Voltage = (Source1 + Source2) ÷ 2
AC_CMMp-p= Peak-to-Peak(High Pass filter (CM_Voltage))
Where:
AV_CMVp-p is the peak-to-peak common mode voltage.
T/nT ratio
The T/nT Ratio measurement reports the amplitude ratio between transition and
non-transition bits.
The measurement calculates the ratios of all non-transition eye voltages (2nd and
subsequent eye voltages after one edge but before the next) to their nearest
preceding transition eye voltage (1st eye voltage succeeding an edge). In the
accompanying diagram, it is the ratio of the Black voltages to the Blue voltages.
The results are given in dB.
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The application calculates the T/nT Ratio using the following equations:
following a rising edge.
following a falling edge.
Where:
vEYE–HI–TRAN is the High voltage at the interpolated midpoint of the first unit
interval following a positive transition.
vEYE–LO–TRAN is the Low voltage at the interpolated midpoint of the first unit
interval following a negative transition.
vEYE–HI–NTRAN is the High voltage at the interpolated midpoint of all unit
intervals except the first following a positive transition.
vEYE–LO–NTRAN is the Low voltage at the interpolated midpoint of all unit
intervals except the first following a negative transition.
m is the index for all non-transition UIs.
n is the index for the nearest transition UI preceding the UI specified by m.
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In a time trend plot of the measurement results, there is one measurement for
each non-transition bit in the waveform (that is the black arrows in the diagram).
High-Low
The High–Low measurement calculates the change in voltage level across a
transition in the waveform.
The application calculates the High–Low using the following equation:
Where:
VHIGH-LOW is the high-low amplitude measurement result.
n is the index of a selected transition.
i is the index of the UI (bit) location preceding the transition.
i+1 is the index of the UI (bit) location following the transition.
VLEVEL= OP[vPERCENT(i)] is the state level of the unit interval (bit period).
OP[• ] is the selected Operation (either Mean or Mode).
vPERCENT is the set of voltage samples over the selected portion (percent) of
the unit interval, ranging from 1% to 100%.
NOTE. If there are no waveform samples that fall within the identified percentage
of the unit interval, the single nearest waveform sample preceding the center
point of the unit interval will be used.
V-Diff-Xovr
The Differential Crossover Voltage measurement (V–Diff–Xovr) calculates the
voltage level at the crossover voltage of a differential signal pair. If there is
timing jitter on one of the pair of signal lines relative to the other, the crossover
point will be modulated by the jitter. The measurement is calculated using the
following equation:
Where:
VCrossover is the crossing voltage.
VSource1 is the voltage of the first source waveform.
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TCrossover is the crossover time, when the Source1 and Source2 waveforms are
equal in voltage.
Overshoot
Overshoot is the maximum peak amplitude above the Reference voltage level
(VREF). Non-differential signals (Single Ended) are required for this
measurement such as DQS (SE) and CK(SE). For DQS signals, Search and Mark
should be enabled.
Related topics.
High mid and low reference voltage levels
Undershoot
Undershoot is the maximum peak amplitude below the Reference voltage level
(VREF). Non-differential signals (Single Ended) are required for this
measurement such as DQS(SE) and CK(SE). For DQS signals, Search and Mark
should be enabled.
Related topics.
High mid and low reference voltage levels
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Cycle max
Cycle Max is a voltage measurement which measures positive peak voltage for
all cycles. It is the maximum voltage for each cycle from the mid level of rise to
the fall slope.
The application calculates this measurement using the following equation:
VCycleMax= Max(f(RiseIndex(i) to FallIndex(i+1))
Where:
I =1 to the valid edge of the last cycle.
f is the function, which finds the maximum sample point in the defined region.
Cycle min
Cycle Min is a voltage measurement which measures negative peak voltage for
all cycles. It is the minimum voltage for each cycle from the mid level of Fall to
the Rise slope.
The application calculates this measurement using the following equation:
VCycleMin= Min(f(FallIndex(i) to RiseIndex(i+1))
Where:
I =1 to the valid edge of the last cycle.
f is the function, which finds the minimum sample point in the defined region.
Cycle Pk-Pk
Cycle Pk-Pk is a voltage measurement which measures the absolute difference
between the maximum and minimum amplitude for every cycle of the waveform.
It calculates the peak-to-peak value for all cycles of the waveform. The peak
value is measured from Fall slope to the next rise if the valid slope is a Fall. The
next peak would be from Rise to next fall slope. The peak-to-peak value is
calculated on all the pairs of minimum and maximum values available.
The application calculates the Cycle Pk-Pk using the following equation:
for consecutive cycles
Where:
VMax(n) is the maximum peak amplitude.
VMin(n) is the minimum peak amplitude.
n is the number of cycles from 1 to the last valid edge.
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Standard-Specific measurements
DDR setup and hold
measurements
The following four measurements are modified versions of the basic Setup and
Hold measurements found on the Time tab. In contrast to the basic measurements
which always use the Mid voltage reference to determine edge times, these
measurements use the High and Low references as required to conform to some
DDR specifications. For all these measurements, the Strobe signal (DQS) is
assigned to Source1 and the Data signal is assigned to Source2.
The measurements with names ending in “–Diff” are appropriate if you have a
have a differential Data Strobe (DQS) signal. Either connect to DQS+ and DQS–
with a differential probe, or acquire these signals with two single-ended probes
and create a (pseudo-) differential signal using a Math expression (for example:
“Math1 = Ch1 – Ch2”). In this case, the data (DQ) signal uses thresholds other
than the mid threshold, but the DQS signal uses a mid threshold set to 0 V.
Check that the DPOJET reference levels for the data source are set to match the
proper values of VIH(ac), VIH(dc), VIL(ac) and VIL(dc) for the DDR
technology that you are measuring. Depending on which edges you choose to
measure (Rising, Falling or Both), you may not need to set up all of these levels.
For more details on reference level setup, refer to DDR Setup/Hold reference
levels: Differential DQS.
The measurements with names ending in “–SE” are appropriate if you have a
single-ended data strobe (DQS) signal. This is allowed in DDR2 but not in
DDR3. In this case, both the clock (DQS) and data (DQ) signals use thresholds
other than the mid threshold.
Check that the DPOJET reference levels for the strobe and data sources are set to
match the proper values of VIH(ac), VIH(dc), VIL(ac), and VIL(dc) for the DDR
technology that you are measuring. Depending on which edges you choose to
measure (Rising, Falling or Both), you may not need to set up all of these levels.
For more details on the reference level setup, refer to DDR Setup/Hold reference
levels: Single-ended DQS.
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DDR Setup/Hold Reference Levels: Differential DQS. For systems with a differential
DQS signal, the waveform reference points for the Setup (tDS) and Hold (tDH)
measurements details are as shown:
For the Strobe channel (Source1), the mid reference level should be set to 0 V
and the High and Low references are not used. The reference levels for the Data
channel (Source2) are mapped to the source configuration panel as follows:
Typical values for the reference levels for some current technologies can be
found here:
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■
DDR2-400, DDR2-533 reference levels
■
DDR2-667, DDR2-800 reference levels
■
DDR3-800 through DDR3-1600 reference levels
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DDR Setup/Hold Reference Levels: Single-Ended DQS. For systems with a singleended DQS signal, the waveform reference points for the Setup (tDS) and Hold
(tDH) measurements details are as shown:
For both the Strobe channel (Source1) and the Data channel (Source2), the
reference levels are mapped to the source configuration panel as follows:
Typical values for the reference levels for some current technologies can be
found here:
■
DDR2-400, DDR2-533 reference levels
■
DDR2-667, DDR2-800 reference levels
■
DDR3-800 through DDR3-1600 reference levels
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DDR2-400, DDR2-533 Reference Levels. The following reference levels are typical
for single-ended signals in DDR2-400 and DDR2-533 technologies.
The best levels depend on many variables, including the supply voltage, probe
point and any spec amendments, so use this information only for general
guidance.
DDR2-667, DDR2-800 Reference Levels. The following reference levels are typical
for single-ended signals in DDR2-667 and DDR2-800 technologies.
The best levels depend on many variables, including the supply voltage, probe
point and any spec amendments, so use this information only for general
guidance.
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DDR3-800 through DDR3-1600 Reference Levels. The following reference levels
are typical for single-ended signals in DDR3-800 through
DDR3-1600 technologies.
The best levels depend on many variables, including the supply voltage, probe
point and any spec amendments, so use this information only for general
guidance.
DDR Setup-SE
The DDR Setup–SE measures the elapsed time between the designated edge of a
data waveform and when the single-ended strobe (DQS) waveform crosses its
own voltage reference level. The closest data edge to the clock edge that falls
within the range limits is used. The strobe is placed on Source1 and the Data is
placed on Source2. This is the base Setup measurement, which does not include
slew-rate derating. Slew-rate derating tables can be found in the applicable
JEDEC specification.
This measurement is identical to the basic Setup measurement except that instead
of using the Mid reference voltage for determining edge times, it uses the High
and Low reference voltages for both the Data and Strobe (DQS). For more details
on the reference voltage setup, refer to DDR Setup/Hold reference levels: Singleended DQS.
The application calculates this measurement using the following equation:
Where:
T Setup is the setup time.
T Main is the Main input (strobe or DQS) crossing time of VRefHighFall (for
falling strobe edges) or VRefLowRise (for rising strobe edges).
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T 2nd is the 2nd input (data or DQ) crossing time of VRefLowFall (for falling
data edges) or VRefHighRise (for rising data edges).
DDR Setup-Diff
The DDR Setup–Diff measures the elapsed time between the designated edge of
a data waveform and when the differential strobe (DQS) waveform crosses its
own voltage reference level. The closest data edge to the clock edge that falls
within the range limits is used. The strobe is placed on Source1 and the Data is
placed on Source2. This is the base Setup measurement, which does not include
slew-rate derating. Slew-rate derating tables can be found in the applicable
JEDEC specification.
This measurement is identical to the basic Setup measurement except that instead
of using the Mid reference voltage for determining edge times, it uses the High
and Low reference voltages for the Data. The Mid reference level is still used for
the Strobe (DQS). For more details on the reference voltage setup, refer to DDR
Setup/Hold reference levels: Differential DQS.
The application calculates this measurement using the following equation:
Where:
TSetup is the setup time.
TMain is the Main input (strobe or DQS) crossing time of VRefMid in the
specified direction.
T2nd is the 2nd input (data or DQ) crossing time of VRefLowFall (for falling
data edges) or VRefHighRise (for rising data edges).
DDR Hold-SE
The DDR Hold–SE measures the elapsed time between the designated edge of
the single-ended strobe (DQS) waveform and the designated edge of a data
waveform. The closest data edge to the clock edge that falls within the range
limits is used. The strobe is placed on Source1 and the Data is placed on Source2.
This is the base Hold measurement, which does not include slew-rate derating.
Slew-rate derating tables can be found in the applicable JEDEC specification.
This measurement is identical to the basic Hold measurement except that instead
of using the Mid reference voltage for determining edge times, it uses the High
and Low reference voltages for both the data and strobe (DQS). For more details
on the reference voltage setup, refer to DDR Setup/Hold reference levels:
Differential DQS.
The application calculates this measurement using the following equation:
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Where:
THold is the hold time.
TMain is the Main input (strobe or DQS) crossing time of VRefLowFall (for
falling strobe edges) or VRefHighRise (for rising strobe edges).
T2nd is the 2nd input (data or DQ) crossing time of VRefHighFall (for falling
data edges) or VRefLowRise (for rising data edges).
DDR Hold-Diff
The DDR Hold–Diff measures the elapsed time between the designated edge of
the single-ended strobe (DQS) waveform and the designated edge of a data
waveform. The closest data edge to the clock edge that falls within the range
limits is used. The strobe is placed on Source1 and the Data is placed on Source2.
This is the base Hold measurement, which does not include slew-rate derating.
Slew-rate derating tables can be found in the applicable JEDEC specification.
This measurement is identical to the basic Hold measurement except that instead
of using the Mid reference voltage for determining edge times, it uses the High
and Low reference voltages for the data. The mid reference level is still used for
the strobe (DQS). For more details on the reference voltage setup, refer to DDR
Setup/Hold reference levels: Differential DQS.
The application calculates this measurement using the following equation:
Where:
THold is the hold time.
TMain is the Main input (strobe or DQS) crossing time of VRefMid in the
specified direction.
T2nd is the 2nd input (data or DQ) crossing time of VRefHighFall (for falling
data edges) or VRefLowRise (for rising data edges).
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DDR tCL(avg))
DDR tCL(avg) is defined as the average low pulse width calculated across 200cycle window of consecutive low pulses.
The application calculates this measurement using the following equation:
Where:
N=200, which is configurable.
Range: 200≤N≤1M
DDR tCK(avg)
DDR tCK(avg) is calculated as the average clock period across 200-cycle
window.
The application calculates this measurement using the following equation:
Where:
N=200, which is configurable.
Range: 200≤N≤1M
DDR2 tDQSCK
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tDQSCK is the DQS output access time from CK or CK#. tDQSCK is measured
between the rising edge of clock before or after the DQS Preamble time.
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The application calculates this measurement using the following equation:
for mid level
Where:
Tn specifies the clock edges.
TDQS(n) specifies the DQS edges.
The edge locations are determined by the mid-reference voltage levels. This is a
skew measurement between the rising edge of DQS and the rising edge of clock.
NOTE. The JEDEC standard specifies that tDQSCK is the actual position of a
rising strobe edge relative to CK, CK#. Hence, DQS should be in phase with CK.
When DQS and CK are not in phase, there could be possibility of probe polarity
interchange. You can overcome this by changing the edge direction to “Opposite
as From” under edges configure tab for Skew measurements.
For more details, refer to the Configuring edges for skew measurement of the
DPOJET online help.
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DDR tDQSQ-Diff
tDQSQ-Diff is the DQS-DQ skew for DQS and associated DQ signals. Set
JEDEC standard reference levels for DQ.
tDQSQ-Diff uses the DPOJET measurement, Setup.
For more details, refer to the Setup of the DPOJET online help.
DDR tDQSS
tDQSS measures the time taken from WRITE event in DDR bus to the first DQS
latching transition. This measurement has two sources. One bus source (B1) and
a DQS source (analog).
Measurement internally sets up Bus search to look for WRITE events. For every
WRITE event in the bus search output, the algorithm finds and associates the first
rising edge of DQS within the DDR Write burst.
Prerequisites for this measurement are: DDR Parallel Bus source, Search and
Mark to be setup for DDR Write search and DPOJET Global tab Qualifier to be
turned On and Qualifier source configured to DDR Write. This measurement is
available only on 64-bit MSO instruments. Measurement gets selected only if
there is a bus source configured.
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DDR tERR(n) and DDR
tERR(m-n)
DDR tERR(n) is defined as the cumulative error across multiple consecutive
cycles from tCK(avg). DDR tERR(m-n) is defined as the cumulative error across
multiple consecutive predefined cycles from tCK(avg).
The application calculates this measurement using the following equation:
Where:
n=2 for tERR(2 per)
n=3 for tERR(3 per)
n=4 for tERR(4 per)
n=5 for tERR(5 per)
6 ≤ n ≤ 10 for tERR(6–10 per)
11 ≤ n ≤ 50 for tERR(11–50 per)
DDR tHZDQ
DDR tHZDQ is a two source timing measurement defined as time duration from
the extrapolated point (at VDD – VDD (34/(50+34)) established by extending the
slope between Vsw1 and Vsw2 to the nearest rising edge of clock.
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DDR tJIT(duty)
DDR tJIT(duty) is defined as the cumulative set of the largest deviation of any
single tCH from tCH(avg) and the largest deviation of any single tCL from
tCL(avg).
The application calculates this measurement using the following equation:
Where:
tJIT(CH) = {tCHi– tCH(avg)}
tJIT(CL) = {tCLi– tCL(avg)}
Where:
i=1 to 200
DDR tJIT(per)
DDR tJIT(per) is defined as the largest deviation of any single tCK from
tCK(avg).
The application calculates this measurement using the following equation:
Where:
i =1 to 200
DDR tLZDQ
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DDR tLZDQ is a two source timing measurement defined as time duration from
the extrapolated point (at VDD = 1.2V) established by extending the slope
between Vsw1 and Vsw2 to the nearest rising edge of clock.
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DDR tCH(avg)
DDR tCH(avg) is defined as the average high pulse width and is calculated
across 200-cycle window of high pulses.
The application calculates this measurement using the following equation:
DDR tRPRE
DDR tRPRE is defined as the width of the READ preamble from the exit of
tristate to the first rising edge on DQS. tRPRE in DDR3–Write bursts uses DDR
tWPRE.
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The application calculates this measurement using the following equation:
Where:
n1 is the start time of the preamble.
n2 is the end time of the preamble.
DDR tWPRE
DDR tWPRE is defined as the width of WRITE preamble from the exit of tristate
to the first rising edge on DQS. This measurement is applicable only for DDR3
generation.
The application calculates this measurement using the following equation:
Where:
n1 is the start time of the preamble.
n2 is the end time of the preamble.
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DDR tPST
DDR tPST is defined as the width of the postamble, from the last falling mid
reference level crossing to the start of an undriven state (as judged by a rising
trend per JEDEC specs), for either a Read or Write burst.
Where:
n1 is the start time of the postamble.
n2 is the end time of the postamble.
DDR over area
DDR Over Area is defined as the area of a triangle for which the base is defined
by the crossings of the configured reference level and the peak is the maximum
voltage level attained between those crossings.
The area of focus is a triangular area in which the start and stop points are
identified as closest to the maximum point in the defined region.
The application calculates this measurement using the equation:
Over Area= 0.5*Base*Height
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Where:
Base is the width of the triangle.
Height is the altitude of the triangle which specifies the maximum sample point
from the triangular base.
DDR under area
DDR Under Area is defined as the area of an inverted triangle for which the base
is defined by the crossings of the configured reference level and the (downward
pointing) peak is the minimum voltage level attained between those crossings.
The area of focus is an triangular area in which the start and stop points are
identified as closest to the maximum point in the defined region.
The application calculates this measurement using the equation:
Under Area= 0.5*Base*Height
Base is the width of the triangle
Height is the altitude of the triangle which specifies the maximum sample point
from the triangular base.
DDR VID(ac)
DDR VID(ac) specifies the AC differential input voltage. This is measured on a
differential voltage DQS signal, which is equivalent to using two single-ended
signals such as DQS and DQS# separately. For more details, refer to High-Low
measurement.
The application calculates this measurement using the following equation:
VID(ac)= Maximum (High,–Low)
Where:
High is the worst-case value from positive to zero.
Low is the worst-case value from negative to zero.
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DDR3 Vix(ac)
DDR3 Vix(ac) is defined as the differential input cross-point voltage measured
between the actual crossover voltage of DQS/DQS and VDD/2. It represents the
differential input cross-point voltage relative to VDD/2 for (CK/CK) or (DQS/
DQS).
The application calculates this measurement using the following equation:
Where:
Vactualcrossover is the crossing between positive and compliment signals (DQS/
DQS)
VRef= VDD/2
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PCIe T-Tx-Diff-PP
PCIe T-Tx-Diff-PP voltage swing calculates the change in voltage level across a
transition in the waveform. It is the peak-to-peak differential voltage swing.
The application calculates this measurement using the following equation:
Where:
VDiff-p-p is the differential peak-to-peak voltage.
VHigh is the maximum voltage calculated between i and i+1 points.
VLow is the minimum voltage calculated between i and i+1 points.
i is the index of the UI (bit) location preceding the transition.
i+1 is the index of the UI (bit) location after the transition.
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PCIe T-TX
PCIe T-Tx-Fall
PCIe T-TX is based on the DPOJET measurement, Eye width. For more details,
refer to the Eye width.
PCIe T-Tx-Fall is the time difference between the VRefLo(20%) reference level
crossing and the VRefHi(80%) reference level crossing on the falling edge of the
waveform. The VRefLo and VRefHi are calculated based on the voltage level of
the previous UI. There are two distinct thresholds corresponding to deemphasized transitions from high to low, and full swing transitions for VRefLo
and VRefHi.
The application calculates this measurement using the following equation:
Where:
TFall is the fall time
TLo– is the VRefLo crossing on the falling edge
THi– is the VRefHi crossing on the falling edge
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PCIe Tmin-Pulse
PCIe Tmin-Pulse (minimum single pulse width TMin-Pulse) is measured from one
transition center to the next.
The application calculates this measurement using the following equation:
Where:
TMin-Pulse is the minimum pulse width
T is the transition center
PCIe DeEmph
PCIe DeEmph is based on the DPOJET measurement, T/nT Ratio. For more
details, refer to the TnT ratio.
NOTE. PCIe DeEmph measurement uses Brick Wall filter.
PCIe T-Tx-Rise
PCIe T-Tx-Rise is the time difference between the VRefHi(80%) reference level
crossing and the VRefLo(20%) reference level crossing on the rising edge of the
waveform. The VRefHi and VRefLo are calculated based on the voltage level of
the previous UI. There are two distinct thresholds corresponding to deemphasized transitions from low to high, and full swing transitions for VRefHi
and VRefLo.
The application calculates this measurement using the following equation:
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Where:
TRise is the Rise time
THi+ is the VRefHi crossing on the rising edge
TLo+ is the VRefLo crossing on the rising edge
PCIe UI
PCIe UI is based on the DPOJET measurement, Period. For more details, refer to
the Period.
NOTE. PCIe UI uses a 3rd order LPF with the cut-off frequency of 198 kHz.
PCIe Med-Mx-Jitter
PCIe Med-Mx-Jitter is the maximum time between the jitter median and the
maximum deviation from the median.
The application calculates this measurement using the following equation:
Where:
TMed-Max-Jitter is the median to max jitter
TJitter-Median is the jitter median
TIE is the Time interval error
PCIe T-RF-Mismch
PCIe T-RF-Mismch (Rise and Fall Time mismatch measurement) is the
mismatch between Rise time (TRise) and Fall time(TFall). Rise time and Fall time
are calculated using the “PCIe T-Tx-Rise” and “PCIe T-Tx-Fall” measurements.
The application calculates this measurement using the following equation:
Where:
TMismatch is the rise and fall time mismatch
TRise is the rise time
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TFall is the fall time
PCIe MAX-MIN ratio
PCIe MAX-MIN Ratio (custom name is PCIe VRX-MAX-MIN Ratio) is defined
as the voltage range ratio over which a particular receiver must operate for the
consecutive UI. Locate the mid edges crossover points. On the rising edge of the
waveform, find the VSWINGMIN. At the VSWINGMIN point, trace back two unit
intervals to find the VSWINGMAX.
The application calculates this measurement using the following equation:
Where:
VSWINGMAX is the maximum voltage swing on the rising edge of the waveform.
VSWINGMIN is the minimum voltage swing on the rising edge of the waveform.
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PCIe SSC PROFILE
PCIe SSC FREQ DEV
PCIe SSC Profile measurement uses the Period measurement with a second order
low pass filter of 1.98 MHz. The PCIe SSC Profile shows the modulation profile
of the Spread Spectrum Clocking. Using the SSC profile, you can find the SSC
modulation rate by using vertical bar cursors and peak-to-peak frequency
deviation by using horizontal bar cursors. The configurations required to be set
are:
■
Constant Clock Mean as the Clock Recovery method
■
Low pass filter to get the SSC components
■
Time Trend Plot for the Period measurement
PCIe SSC FREQ DEV is defined as the SSC frequency deviation in ppm (parts
per million).
■
Use the PCIe SSC Profile measurement to locate the mid edge cross points.
■
Calculate the HIGH value between the n and n+1 edge and the LOW value
between n+1 and n+2 edges.
The application calculates the measurement using the equation:
FREQ DEVIATION = HIGH–LOW
PCIe AC common mode
The AC Common Mode Voltage measurement is the common mode voltage
between two single-ended signals. AC is defined as all the frequency components
above the cutoff frequency (30 kHz).
The application calculates this measurement using the following equations (based
on two single-ended sources from the DUT):
CM_Voltage = (Source1 + Source2) ÷ 2
AC_CMMp-p= Peak-to-Peak(High Pass filter (CM_Voltage))
Where:
AV_CMVp-p is the peak-to-peak common mode voltage.
GDDR5 tBurst-CMD
GDDR5 tBurst-CMD (WCK, DQ, CMD_BUS) is defined as the elapsed time
between the last data element of a READ or WRITE burst to the next bus state.
The next bus state depends on the command of interest which is configured in the
search. This measurement is available only on 64-bit MSO instruments.
This measurement requires that the Bus source and DPOJET Qualifiers should be
turned on for DDR read or DDR Write searches.
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GDDR5 tCKSRE
The GDDR5 tCKSRE measurement is a Bus measurement for the
GDDR5 standard. This measures valid CK clocks required after the self refresh
entry (SRE). This measurement is available only on 64-bit MSO instruments. The
measurement requires Clock source and Bus as inputs.
T0 = time at which clock stops toggling, after self refresh entry. T1 = Rising edge
of clock where SRE command gets registered.
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GDDR5 tCKSRX
The tCKSRX measurement is a Bus measurement for the GDDR5 standard. This
is the time elapsed between the SRX command to valid clock cycles. The clock
cycles get into continuous 1s or CK (#) 0s after the SRX. After the SRX
command the algorithm searches forward on the CK source to lock onto the clock
cycles with continuous 1s. This measurement is only available on 64-bit MSO
instruments.
Tb0 = time at which clock starts toggling, before self-refresh exit. Tb2 = Rising
edge of clock where SRX command gets registered.
T-TX-DDJ
T-TX-DDJ is defined as the time delta between the PDF’s mean for each zero
crossing point and the corresponding recovered clock edge.
■
Recover the clock to convert it to a bit stream.
■
Find the repeating patterns to locate Pattern Length and Pattern Repeat
Count.
■
For k=0 to Pattern_Length, find the correlated jitter.
For i=0 to Pattern_Repeat_Count, find the edge jitter using:
EdgeJitteri = Edgei – Recovered Edgei
Correlated Jitterk = mean (EdgeJitter)
The application calculates the measurement using the equation:
Data dependent Jitter (T-TX-DDJ) = max (CorrelatedJitter) – min
(CorrelatedJitter)
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T-TX-UTJ
T-TX-UTJ is referenced to a recovered data clock generated by means of a CDR
tracking function. Uncorrelated total jitter may be derived after removing the
DDJ component from each PDF and combining the PDFs for all edges in the
pattern.
■
Recover the clock to convert it to a bit stream.
■
Find the repeating patterns to locate Pattern Length and Pattern Repeat
Count.
■
For k=0 to Pattern_Length, find the correlated jitter.
For i=0 to Pattern_Repeat_Count, find the edge jitter using:
EdgeJitteri = Edgei – Recovered Edgei
Correlated Jitterk = mean (EdgeJitter)
■
Find uncorrelated jitter max and min values by removing the correlated
jitter values using:
Max_Uncorrelated_Jitter= Max ( Max_Uncorrelated Jitter, ( EdgeJitter
– Corrolated Jitterk))
Min_Uncorrelated_Jitter= Max ( Min_Uncorrelated Jitter, ( EdgeJitter –
Corrolated Jitterk))
■
Find the absolute maximum uncorrelated jitter (max_abs_uj).
■
Use the absolute value to create a histogram plot with appropriate bin values
(used for creating PDFs).
■
Create PDF and combine the PDFs of all edges.
■
Convert the PDF into Q scale and draw a gaussian line (Gaussian Fit) to
calculate the vertical opening on left and right side of the Q-scale curve.
The application calculates the measurement using the equation:
Uncorrelated Total Jitter (T-TX-UTJ) = Vertical left opening– Vertical right
opening
T-TX-UDJDD
T-TX-UDJDD is defined as the uncorrelated jitter at the zero crossing point and
at the corresponding recovered clock edge.
■
Recover the clock to convert it to a bit stream.
■
Find the repeating patterns to locate Pattern Length and Pattern Repeat
Count.
■
For k=0 to Pattern_Length, find the correlated jitter.
For i=0 to Pattern_Repeat_Count, find the edge jitter using:
EdgeJitteri = Edgei – Recovered Edgei
Correlated Jitterk = mean (EdgeJitter)
■
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Find uncorrelated jitter max and min values by removing the correlated
jitter values using:
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Max_Uncorrelated_Jitter= Max ( Max_Uncorrelated Jitter, ( EdgeJitter
– Corrolated Jitterk))
Min_Uncorrelated_Jitter= Max ( Min_Uncorrelated Jitter, ( EdgeJitter –
Corrolated Jitterk))
T-TX-UPW-TJ
■
Find the absolute maximum uncorrelated jitter (max_abs_uj).
■
Use the absolute value to create a histogram plot with appropriate bin values
(used for creating PDFs).
■
Create PDF and combine the PDFs of all edges.
■
Convert the PDF into Q scale and draw a gaussian line (Gaussian Fit) to
calculate the vertical opening on left and right side of the Q-scale curve.
■
Calculate the Uncorrelated Total Jitter (T-TX-UTJ) = Vertical left opening–
Vertical right opening
■
Find where the gaussian line crosses the zero crossing and calculate T-TXUDJ-DD.
T-TX-UPW-TJ is defined as an edge-to-edge phenomenon on consecutive edges.
■
Recover the clock to convert it to a bit stream.
■
Find the repeating patterns to locate Pattern Length and Pattern Repeat
Count.
■
For k=0 to Pattern_Length, find the correlated jitter.
For i=0 to Pattern_Repeat_Count, find the edge jitter using:
EdgeJitteri = Edgei – Recovered Edgei
Correlated Jitterk = mean (EdgeJitter)
■
Replicate the correlated jitter for each of the repeated pattern.
■
Calculate the mean_pwj referencing to a fixed leading edge and having jitter
contributions from both edges appear at the trailing edge.
■
Use the mean_pwj value to find a histogram plot to accommodate all the
PWJ values to create the PDF.
■
Calculate the Q-Scale extrapolation for this PWJ-PDF.
■
Calculate the vertical opening on left and right side of the Q-scale curve.
■
Calculate the Uncorrelated Total Power Jitter (T-TX-PWJ-TJ) = Vertical left
opening– Vertical right opening
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T-TX-UPW-DJDD
T-TX-UPW-DJDD is defined as the Uncorrelated Pulse Width Jitter (PWJ) at the
zero crossing.
■
Recover the clock to convert it to a bit stream.
■
Find the repeating patterns to locate Pattern Length and Pattern Repeat
Count.
For k=0 to Pattern_Length, find the correlated jitter.
For i=0 to Pattern_Repeat_Count, find the edge jitter using:
EdgeJitteri = Edgei – Recovered Edgei
Correlated Jitterk = mean (EdgeJitter)
■
Replicate the correlated jitter for each of the repeated pattern.
■
Calculate the PWJ referencing to a fixed leading edge and having jitter
contributions from both edges appear at the trailing edge and calculate the
mean_pwj.
■
Use the absolute value to create a histogram plot with appropriate bin values
(used for creating PDFs).
■
Create PDF and combine the PDFs of all edges.
■
Convert the PDF into Q scale and draw a gaussian line (Gaussian Fit) to
calculate the vertical opening on left and right side of the Q-scale curve.
The application calculates the measurement using the equation:
Uncorrelated Total Jitter (T-TX-UTJ) = Vertical left opening– Vertical right
opening
V-TX-EQ-NO
V-TX-EIEOS
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V-TX-EQ-NO is defined by setting c-1 and c+1 to zero and measuring the peakto-peak voltage on the 64-ones/64-zeroes segment of the compliance pattern.
■
Find the 64 zeros/64 ones between two consecutive edges.
■
Find the voltage between the 57th to 62nd UI of both positive and negative
cycle.
■
Calculate the average voltage of both positive and negative cycle.
■
Find the voltage difference between positive and negative cycles.
V-TX-EIEOS is defined by setting c+1 coefficient value of –0.33 and a c-1
coefficient value of 0.0 and measuring the peak-to-peak voltage on the 8-ones/8zeroes segment of the compliance pattern, where the pattern is repeated for a total
of 128 UI.
■
Find the 8 zeros/8 ones between two consecutive edges.
■
Find the voltage between the 3rd to 7th UI of both positive and negative cycle.
■
Calculate the average voltage of both positive and negative cycle.
■
Find the voltage difference between positive and negative cycles.
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ps21TX
Package loss (ps21TX) is measured by comparing the 64-zeroes/64-ones PP
voltage (V111) against a 1010 pattern (V101)
■
Find the 1010 bit pattern (V101) for 64 UI in the compliance pattern.
■
Find 64 ones/64zeros bit pattern (V111) adjacent to 1010 pattern.
■
Find the 50,52 and 54th bits from the positive UIs and 49,51 and 53rd bits
from the negative UIs of the 1010 bit pattern.
■
Calculate the peak-to-peak voltage difference between positive and negative
UIs.
■
Find the voltage between 57th UI to 62nd UI of both positive and negative
cycle.
■
Calculate the average voltage of the positive and negative cycle.
■
Find the voltage difference between positive and negative cycles.
The application calculates this measurement using the following equation:
Package Loss Ratio = 20log10(V101/V111)
V-Tx-Boost
USB VTx-Diff-PP
V-Tx-Boost is when the c-1 and c+1 are nonzero and measuring the PP voltage
on the 64-ones/64-zeroes segment of the compliance pattern and with immediate
single transition bit voltage.
■
Find 64-ones/64-zeros bit pattern.
■
Find the voltage between 57th UI to 62nd UI of positive cycle and negative
cycle in V111 pattern.
■
Calculate the average voltage of the positive and negative cycle (V111) in
each 4680 pattern.
■
Add all averaged voltages for entire waveform.
■
Average again by number of repetitions of 4680 bit patterns in the entire
waveform. This is Vb.
■
Find Single UI pulse after 64-ones/64-zeros.
■
Calculate the peak-to-peak voltage difference between the positive and
negative UI (V1UI).
■
Average all V1UI for the entire waveform.
■
Calculate the VBoost = 20log10(V1UI/V111).
VTx-Diff-PP voltage swing calculates the change in voltage level across a
transition in the waveform. It is the peak-to-peak differential voltage swing.
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The application calculates this measurement using the following equation:
Where:
VDiff-p-p is the differential peak-to-peak voltage.
VHigh is the maximum voltage calculated between i and i+1 points.
VLow is the minimum voltage calculated between i and i+1 points.
i is the index of the UI (bit) location preceding the transition.
i+1 is the index of the UI (bit) location after the transition.
USB TCdr-Slew-Max
Slew rate measurement finds the peak-to-peak period jitter. Period jitter can be
obtained by taking the first difference of the filtered phase jitter. The application
uses the Period measurement with an LPF of 1.98 MHz to find the period jitter. It
calculates the phase jitter by taking the cumulative sum of the period jitter. Filters
the phase jitter with the CR transfer function using the following equation:
The filtered period jitter is obtained from the phase jitter to calculate peak-topeak period jitter.
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USB Tmin-Pulse-Tj
Tmin-Pulse-Tj (minimum single pulse width TMin-Pulse) is measured from one
transition center to the next including all jitter sources.
The application calculates this measurement using the following equation:
Where:
TMin-Pulse is the minimum pulse width
T is the transition center
USB Tmin-Pulse-Dj
USB SSC MOD RATE
USB Tmin-Pulse-Dj is defined as the minimum pulse width with only
deterministic jitter components.
■
Plot the time trend for the TIE measurement.
■
Take the FFT of the TIE time trend to get the TIE spectrum. Then separate
the RJ and DJ values from the spectrum.
■
Take the IFFT of the TIE spectrum without the RJ components and
reconstruct the clock based on the TIE trend without the RJ components.
■
Find the minimum pulse width within the reconstructed clock.
USB SSC MOD RATE is defined as the SSC modulation rate in terms of Hz. Use
the SSC Profile measurement to locate the mid edge crossover points. Determine
the time difference between the consecutive mid reference voltage levels as
shown:
Δt= Tn+1–Tn
Where:
Tn is the VREFmid crossing time
Tn+1 is the n+1 VREFmid crossing time
The application calculates this measurement using the following equation:
Modulation Rate= 1/Δt
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USB SSC FREQ-DEV-MAX
USB SSC FREQ DEV MAX is defined as the maximum frequency shift as a
function of time. It represents the frequency deviation in terms of ppm (parts per
million).
■
Find the 50% edges on the SSC profile.
■
Calculate the HIGH value between the n and n+1 edge.
■
Find the Maximum frequency deviation as HIGH.
The application calculates the measurement using the equation:
Freq Dev Max(ppm)= ((Maximum Freq–Nominal Data Rate)/Nominal Data
Rate)* 1e6
USB SSC FREQ-DEV-MIN
USB SSC FREQ DEV MIN is defined as the minimum frequency shift as a
function of time. Represents the frequency deviation in terms of ppm (parts per
million).
■
Find the 50% edges on the SSC profile.
■
Calculate the LOW value between the n and n+1 edge.
■
Find the Maximum frequency deviation as LOW.
The application calculates the measurement using the equation:
Freq Dev Min(ppm)= ((Minimum Freq–Nominal Data Rate)/Nominal Data
Rate)* 1e6
USB SSC PROFILE
USB UI
USB SSC Profile measurement uses the Period measurement with a second order
low pass filter of 1.98 MHz. The USB SSC Profile shows the modulation profile
of the Spread Spectrum Clocking. Using the SSC profile, you can find the SSC
modulation rate by using horizontal cursors and peak-to-peak frequency
deviation by using vertical cursors. The configurations required to be set are:
■
Constant Clock Mean as the Clock Recovery method
■
Low pass filter to get the SSC components
■
Time Trend Plot for the Period measurement
USB UI is based on the DPOJET measurement, Period. For more details, refer to
the Period.
NOTE. USB UI uses a 3rd order LPF with the cut-off frequency of 198 kHz.
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USB AC common mode
The USB AC Common Mode Voltage measurement is the common mode voltage
between two single-ended signals. AC is defined as all the frequency components
above the cutoff frequency (30 kHz).
The application calculates this measurement using the following equations (based
on two single-ended sources from the DUT):
CM_Voltage = (Source1 + Source2) ÷ 2
AC_CMMp-p= Peak-to-Peak(High Pass filter (CM_Voltage))
Where:
AV_CMVp-p is the peak-to-peak common mode voltage.
Jitter separation
Jitter analysis through RJDJ separation
Many of the jitter measurements are based on the concept of RJ-DJ separation.
The application begins with the measured jitter-versus-time (as represented by
the TIE measurement array) and analytically determines the random and
deterministic components of the jitter. The deterministic part is further separated
into independent subcomponents with specific characteristics.
The random jitter (RJ) is assumed to be zero-mean Gaussian, and is assumed to
have a flat spectrum when viewed in the frequency domain. The measured RJ is
fitted to a Gaussian mathematical model, which is parameterized by its standard
deviation. Using the mathematical model for RJ, statistically probable jitter
extremes may be predicted for much greater populations than actually measured.
The deterministic jitter (DJ) is predictable and can be generated consistently
given known circumstances. The various DJ measurements each report the peakto-peak value of the corresponding DJ subcomponent.
Once all the jitter components have been identified and the random jitter has been
converted to a mathematical model, the components can be reassembled such that
performance may be extrapolated to extremely low bit error rates. The
probabilistic Total Jitter (TJ@BER) and probabilistic Eye Width (Width@BER)
are examples of such measurements. The reported values are predictions that
correspond to a user-specified Bit Error Rate, rather than observed values.
Two approaches are supported for performing jitter separation. The first method
is based on spectrum analysis. It is only possible when the data pattern is
repetitive. A clock waveform is always repetitive. Other repetitive testing data
patterns are used, such as the K28.5 data pattern. Patterns may have rather long
repetition lengths; for example, the CJTPAT pattern is 2640 bits. When using this
method, you must specify the pattern length, and you will receive a warning if the
pattern length appears to differ from that specified.
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The second RJ-DJ separation method, known as arbitrary pattern analysis, may
be used when the data pattern is not necessarily repetitive. This method works by
correlating deterministic jitter observed over many repetitions with the bit pattern
within a time-domain window surrounding each observation.
RJ-DJ separation via
spectrum analysis
When the source waveform represents a repeating data pattern, Deterministic
Jitter (DJ) has a frequency spectrum of impulses. The impulses due to the data
pattern are equally spaced and occur at predictable frequencies related to the
pattern length and bit rate. Specifically, the pattern-related jitter impulse must
occur at multiples of fo/N, where fo is the data bit rate and N is the data pattern
length. Other spectral impulses may occur due to periodic jitter not correlated
with the data pattern.
To obtain measurements of DJ and RJ, all the components of the jitter spectrum
that exceed the noise floor by a chosen margin are attributed to deterministic
jitter. Those components that fall at the frequency increment corresponding to the
pattern length are identified as data-dependent jitter, and those occurring at other
frequencies are attributed to uncorrelated periodic jitter. The remaining spectral
noise floor (appropriately normalized to account for the removed deterministic
jitter) is integrated to predict the standard deviation of the underlying Gaussian
random noise process.
Once the spectral components corresponding to each deterministic jitter type
have been identified, each component is inverse-transformed back to the time
domain. From these waveforms, the peak-to-peak jitter for each component is
determined. For the random jitter, the RMS deviation is directly computable from
the standard deviation of the Gaussian model.
RJ-DJ separation for
arbitrary patterns
When the data pattern borne by the source waveform is not cyclically repeating,
any periodic jitter still has a frequency spectrum consisting of impulses but this is
not true of the data-dependent jitter.
In this case, analysis of the data-dependent jitter may proceed based on the
assumption that any given bit is affected by a finite (and relatively small) number
of preceding bits. By averaging all events for which a given bit is preceded by a
particular bit sequence, the data-dependent jitter attributable to that bit sequence
is obtained. This is because PJ and RJ are not correlated to a particular data
sequence and thus are averaged out.
If each bit is assumed to be affected by N preceding bits, there are a total of 2N
possible data sequences. The sequence length N is a configurable parameter. To
get statistically sound average values for the data-dependent jitter, a minimum
population of observations is required for each individual pattern that occurs at
least once. This population limit is also configurable by the user.
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By the above means, the data-dependent jitter is characterized. Once
characterized, the data-dependent jitter, on a bit-by-bit basis, may be removed
from the original jitter versus time record. The remaining jitter is composed of
periodic and random jitter. This jitter is transformed into the frequency domain,
and the spectral analysis approach is used to separate the impulsive periodic jitter
from the broad noise floor of random jitter.
Separation of NonPeriodic jitter (NPJ)
Bounded Uncorrelated Jitter (BUJ) refers to all bounded jitter that is not
correlated to the data pattern on the waveform. Thus, it excludes DDJ, DCD and
RJ. It can be further subdivided into PJ (which is deterministic, and easily
recognized using a spectral approach) and Non-Period Jitter (NPJ).
Depending on its precise nature, NPJ is often difficult to distinguish from RJ. It
typically cannnot be isolated using frequency domain techniques, so a different
domain is used. The important difference between RJ and NPJ is that RJ has a
Gaussian distribution (with unbounded tails) whereas NPJ is bounded by
definition. This fact is used as a basis for separation.
In DPOJET, the jitter separation algorithms are modified as follows when the
Spectral + BUJ method is selected:
1. Data-Dependent Jitter (DDJ) and Duty-Cycle jitter (DCD) are first removed
using either a spectral approach for repeating patterns or a correlation
approach for arbitrary data patterns.
2. PJ is identified and removed using a spectral approach.
3. The remaining jitter is assumed to contain (Gaussian) RJ and possibly NPJ.
(In the Spectral Only method of jitter analysis, no further processing is done
and this jitter is reported as RJ.)
4. When Spectral + BUJ processing is selected, the RJ + NPJ jitter is collected
into a histogram that is typically accumulated over multiple waveform
acquisitions. When the (user-configurable) minimum histogram population
has been acquired, the histogram is converted to an estimate of the
Cumulative Density Function (CDF) and plotted using the Q-scale for the
vertical axis. The Q-scale plot has the property that a true Gaussian
distribution appears as a straight line, with a slope equal to 1/σ (where σ is
the standard deviation of the Gaussian distribution). If the distribution is a
mixture of a true Gaussian plus some bounded distribution, the plotted curve
has left and right extremes that asymptotically approach straight lines with a
slope of 1/σ. The horizontal offset between the two asymptotes represents the
dual-dirac magnitude of the NPJ.
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Estimation of TJ@BER
and eye Width@BER
One of the outcomes of the RJ-DJ separation was a mathematical model for
random jitter’s probability density function (PDF) and measured values for the
PDFs of the deterministic jitter components. Since all of these components are
assumed to be statistically independent, the PDF of the total jitter can be
calculated by convolution.
Integration of the PDF yields the cumulative distribution function (CDF), which
can then be used to create the bit error rate curve (bathtub curve). Based on the
bathtub curve, the eye opening (Width@BER) and eye closure (TJ@BER) can be
estimated for a given bit error rate.
The application calculates the eye opening at the specified BER using the
following equation:
Eye opening = 1–TJ@BER when TJ@BER is less than one Unit Interval
Jitter estimation using
Dual-Dirac models
Jitter estimation based on RJ-DJ separation depends in part on the specific jitter
components modeled. For the purposes of analyzing jitter and identifying root
cause, it is very useful to identify components as specifically as possible. But for
the purposes of determining compliance, it has been found that a simplified jitter
model yields results that are more consistent across different measurement
instruments and different vendors.
A simplified model that has found acceptance in several industry standards is
known as the Dual-Dirac model. This is because the probability density function
(PDF) of all the deterministic jitter is replaced with a PDF consisting of two
Dirac functions such that the total jitter and eye opening at very low bit error
rates is unchanged. The Random Jitter and Deterministic Jitter values derived
from this model are identified as RJ–δδ and DJ–δδ, respectively.
Two slightly different Dual-Dirac models have been defined. Both models begin
with a jitter versus BER (bathtub) curve, either created from a full jitter analysis
based on RJ-DJ separation, or from direct measurement of error rate versus
sample point offset. The two models differ in how the RJ–δδ and DJ–δδ values
are extracted from the curve.
For the Fibre-Channel standard, values for RJ–δδ and DJ–δδ are chosen such that
the Dual-Dirac bathtub curve exactly matches the measured curve at the BER =
10-5 and BER=10-9 points.
For the PCI Express and FB-DIMM standards, the bathtub curve is re-plotted
using a different y-axis. Instead of directly plotting against the log of the BER,
the y-axis is converted to the Q-scale. The BER to Q-scale transformation was
designed such that Gaussian distributions are converted to straight lines, with a
slope that is directly related to the standard deviation of the Gaussian.
When using the Dual-Dirac jitter measurements, it is critical that you select the
model that matches the applicable standard. This may be configured in the
DPOJET preferences, which are found under Analyze > Jitter and Eye Analysis
(DPOJET) > Preferences, on the Measurement tab.
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Joint Jitter/Noise analysis
Differences between JitterOnly and Jitter+Noise
analysis
Traditionally, jitter has been analyzed by detecting edge crossings at a voltage,
current or optical power reference level and then analyzing the distribution of
these edge times relative to a reference clock. Based on various properties of the
jitter distribution (observed in the time, frequency and statistical domains), the
jitter has been separated into categories or components that exhibit well-known
behaviors. This allows a mathematical model of the jitter to be constructed,
which can then be used to extrapolate jitter behavior for higher populations of
bits than were actually measured. In this process, the shape of the analog
waveform between edge crossings is entirely ignored.
In Joint Jitter/Noise Analysis, the entire analog waveform is analyzed. The
process is analogous in many ways to Jitter-Only analysis, but the mathematical
model for jitter and noise behavior is more thorough and better fits the physical
world. For example, in addition to the familiar jitter components (RJ, PJ, DDJ)
there are corresponding noise components (RN, PN, DDN). Jitter is still analyzed
at points where the waveform crosses a horizontal reference line, and Noise is
analyzed where the waveform crosses a vertical reference line once each unit
interval. These two reference planes are where the model parameters (RJ – DDJ
and RN – DDN) are determined, although the process of determining the
parameter values involves compensating for effects of jitter on noise and vice
versa.
Because both techniques use parameterized mathematical models to extrapolate
behavior, they will not yield identical results (but should be very close). Consider
an analogy: You could measure the area of a circle by splitting the circle into a
number of narrow wedge-shaped triangles with their points all at the center of the
circle, and adding the areas of the triangles. Or you could estimate the circle’s
area by placing a fine rectangular grid on the circle and counting the number of
squares that were mostly inside the circle. Both methods will yield a good
estimate but the two models won’t give the same answer.
Because the Jitter-Only model does not consider vertical effects, there are some
aspects of eye closure to which the jitter-Only method is entirely blind but the
Jitter+Noise method models well. The Jitter-Only method does not provide any
noise measurement values at all, for obvious reasons. And the Jitter+Noise
method exposes how noise is manifested as jitter, and jitter as noise, which is
helpful in identifying root cause.
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Use of Jitter+Noise
analysis when DJAN is not
enabled
The DJAN option enables noise measurements such as TN@BER, RN and DN in
DPOJET. When you have enabled only DJA (DPOJET Advanced) option, then
you may still select “Jitter+Noise” as the analysis method on the DPOJET
Preferences > Jitter Decomp menu. Then the DPOJET uses the more complex
Jitter + Noise parameter model and processing, but does not allow noise
measurements to select and run. Noise measurements can be selected and run
when you enable DJAN.
It may seem pointless to select the Jitter+Noise analysis method if the noise
measurements are not accessible. The Jitter+Noise uses more complete model,
and the jitter values may change slightly, or even markedly in rare cases.
One example is an eye that is closed at the target BER due to voltage ring-back in
the middle of the eye. In that case, the traditional Jitter-Only method can entirely
miss the noise induced eye closure but the Jitter+Noise approach will recognize
it. Also, selection of the Jitter+Noise model with DJA can be useful if you are
trying to compare jitter measurement results with a peer who is using a scope
with the DJAN option enabled.
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Basic steps in joint Jitter
+Noise analysis
The process of performing Jitter+Noise analysis includes these major steps:
1. Perform clock recovery to identify a reference clock representing the ideal
transition times. This process also yields the received Boolean bit stream.
2. Measure the exact instant in time where each data transition (edge) occurs.
3. Measure the slew rate at each of these edges.
4. Measure the exact amplitude at the center (50% point) of each bit.
5. Measure the slew rate at each of these bit centers.
6. Perform a joint analysis on the prior four data sets to decouple the effects of
jitter on noise and vice versa.
7. Considering the entire analog waveform (not just the edges and bit centers),
derive the “correlated waveform”. This is the waveform the reflects channel
effects (low-pass filtering, reflections) while filtering out variations
uncorrelated to the data pattern.
8. Compare the edge times from step 2 with the clock times from step 1 to
derive TIE (Time Interval Error). Use spectral analysis, time analysis and Qscale analysis to derive model parameters such as RJ and PJ. Please see the
various topics under Jitter analysis through RJ-DJ separation for a more
thorough description of this process.
9. Compare the bit amplitudes from step 3 with the ideal bit stream (derived
from the received Boolean bit stream and the nominal high and low bit
amplitudes). Use spectral analysis, time analysis and Q-scale analysis to
derive model parameters such as RN and PN. See Noise Model Component
Interrelationships.
10. Use two-dimensional convolution to combine the effects of all jitter an noise
model parameters into a statistical model of uncorrelated noise. This includes
RJ, PJ, NPJ, RN, PN and NPN.
11. Convolve the model of uncorrelated jitter+noise with the correlated
waveform to create a model of the overall eye diagram’s true PDF.
12. Integrate the PDF of step 11 from top to bottom (for ‘0’ bits only) to derive
the ‘0’ bit CDF. Perform a complimentary operation to derive the ‘1’ bit
CDF.
13. Superimpose the CDFs of steps 11 and 12 to get the BER eye: analogous to
the bathtub curve, except two-dimensional. (In fact, the jitter bathtub or the
noise bathtub can be derived directly from the BER Eye by slicing it either
horizontally or vertically, respectively.)
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Noise model component
interrelationships
The figure below depicts graphically how the various noise model parameters
relate to each other. It is only the upward-reaching portions of the lower models
and the downward-reaching portions of the upper models that contribute to eye
opening (or closure), and this is reflected in how the DDN, DN and TN@BER
values are calculated.
Results
The application calculates statistics for all selected measurements. The
application displays the following statistics in the Results menu:
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■
Mean
■
Std Dev (Standard Deviation)
■
Max (Maximum Value)
■
Min (Minimum Value)
■
p-p (Peak-to-Peak)
■
Population
■
Max-cc (Maximum positive cycle-to-cycle variation)
■
Min-cc (Maximum negative cycle-to-cycle variation)
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Mean
Standard Deviation
The application calculates the mean value using the following equation:
The application calculates the standard deviation using the following equation:
It may seem odd that the equation for the estimate of the Standard Deviation
contains a 1/(N-1) scaling factor. If you knew the true mean of X and used it in
place of the estimated mean X then you would, in fact, scale by 1/N. But, X is an
estimate and is likely to be in error (or bias), causing the estimate of the Standard
Deviation to be too small if scaled by 1/N. This is the reason for the scaling
shown in the equation. (Refer to Chapter 9.2 in A. Papoulis, Probability, Random
Variables, and Stochastic Processes, McGraw Hill, 1991.)
NOTE. RMS value can be calculated using the relation (rms)= (mean value)+
(stddev).
Maximum Value
The application calculates maximum value using the following equation:
Max(X) = Most Positive Value of X
Minimum Value
The application calculates minimum value using the following equation:
Min(X) = Most Negative Value of X
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p-p
The application calculates peak-to-peak using the following equation:
p-p(X) = Max(X )– Min(X)
Population
Population is the total number of events or observations over which the other
statistics were calculated.
Population (X) = N
Max-cc
The application calculates Max-cc using the following equation:
Max-cc(X) = Max(XCC)
Where:
XCC is the first difference of X.
Min-cc
The application calculates Min-cc using the following equation:
Min-cc(X) = Min(XCC)
Where:
XCC is the first difference of X.
334
DPOJET Printable Application Help
GPIB commands
About the GPIB program
You can use remote GPIB commands to communicate with the DPOJET
application. An example of a GPIB program that can execute the DPOJET
application is included with the application in C:\Users\Public\Tektronix
\TekApplications\DPOJET\Examples.
The example shows how a GPIB program executes the application to do the
following tasks:
1. Start the application.
2. Recall a setup.
3. Take a measurement.
4. View measurement results and plots.
5. Exit the application.
NOTE. Commands are not case and space sensitive. Your program will operate
correctly even if you do not follow the capitalization and spacing precisely.
GPIB reference materials
To use GPIB commands with your oscilloscope, you can refer to the following
materials:
■
The GPIB Program Example in C:\Users\Public\Tektronix\TekApplications
\DPOJET\Examples for guidelines to use while designing a GPIB program.
■
The Parameters topics for range of values, minimum units and default values
of parameters.
■
The programmer information in the online help of your oscilloscope.
DPOJET Printable Application Help
335
GPIB commands
Argument types
The syntax shows the format that the instrument returns in response to a query.
This is also the preferred format when sending the command to the instrument
though any of the formats will be accepted. This documentation represents these
arguments as follows:
Table 85: Argument types
Symbol
Meaning
<NR1>
Signed integer value.
<NR2>
Floating point value without an exponent.
<NR3>
Floating point value with an exponent.
double
Double precision floating point with exponent.
DPOJET: ADDMeas
This set-only command adds the specified measurement to the bottom of the
current DPOJET list of measurements and will appear in the results summary
page.
Syntax
336
DPOJET:ADDmeas {PERIod | CCPeriod | FREQuency | NPERiod | PWIdth |
NWIdth | PDUTy | NDUTy | PCCDuty | NCCDuty | TIE | RJ | RJDirac | TJber |
DJ | DJDirac | PHASENoise | DCD | DDJ | PJ | J2 | J9 | SRJ | FN | RJH | RJV |
PJH | PJV | RN | RNV| RNH | DN | DDN | DDN_1 | DDN_0 | PN | PNV | PNH |
NPN | TNBER | NOISESUMMARY | UNITAMPLITUDE | RISEtime | SETup |
HIGHTime | FALLtime | HOLD | LOWTime | SKEW | HEIght | WIDth |
MASKHits | WIDTHBer | HEIGHTBer | COMmonmode | HIGH | TNTratio |
HIGHLOW | LOW | VDIFFxovr | DDRSETUPSe | DDRSETUPDiff |
DDRHOLDSe | DDRHOLDDiff | DDRTCLaverage | DDRTJITDuty |
DDRTCKaverage | DDRTDQSS | DDRTERrn | DDRTJITper | DDRTCHaverage
| DDRTERRMN | RISESLEWrate | FALLSLEWrate | OVERShoot |
UNDERShoot | CYCLEPktopk | DDRTRpre | DDRTPst | CYCLEMIn |
CYCLEMAx | ACCommonmode | DDROverarea | DDRTWpre | DDRVIDac |
DDR3VIXac | JITTERSummary | PCIETTXDiffpp | PCIEDEemph | PCIETTx |
PCIETTXRise | PCIETTXFall | PCIEUI | PCIETMinpulse | PCIEMEdmxjitter |
PCIETRfmismch | PCIESSCFReqdev | PCIEMAXMINratio | PCIESSCPROFile |
PCIEVEye | PCIETTXUTJ | PCIETTXUDJDD | PCIETTXUPWTJ |
PCIETTXUPWDJDD | PCIETTXDDJ | PCIEVTXBOOST | PCIEVTXNOEQ |
PCIEVTXEIEOS | PCIEPS21TX | PCIEACCommonmode | VTXDiffpp |
TMINPULSETJ | TCDRslewmax | USBUI | USBACCommonmode |
TMINPULSEDJ | DDR2TDQSCK | GDDR5TBursttocmd | GDDR5TCKSRX |
GDDR5TCKSRE | QFACTOR | EYELOW | EYEHIGH | TCMDTOCMD |
TIMEOUTSIDELEVEL | SSCFREQDEVMAX | SSCFREQDEVMIN |
SSCFREQDEV |SSCMODrate | SSCPROfile | USBSSCFREQDEVMAX |
USBSSCFREQDEVMIN | USBSSCMODrate | USBSSCPROFile |
AUTOFITMaskhits}
DPOJET Printable Application Help
GPIB commands
Inputs
Outputs
Same as syntax for measurement options.
None
DPOJET:APPLYAll
This command applies configuration of specified type of the specified DPOJET
measurement to all other DPOJET measurements.
Syntax
DPOJET: APPLYAll {FILTers | CLOCKRecovery| RJDJ}, MEAS<x>
Inputs
{FILTers | CLOCKRecovery| RJDJ}, MEAS<x>
For example: DPOJET:APPLYAll FILTers, MEAS2
DPOJET:BURSTConfig:BUS
This command sets or queries the required Bus source.
Syntax
DPOJET:BURSTConfig:BUS <string>
DPOJET:BURSTConfig:BUS?
Inputs
<string>
Outputs
<string>
DPOJET Printable Application Help
337
GPIB commands
DPOJET:BURSTConfig:CSACTIve
This command sets or queries the Active selection for the Chip select source.
Syntax
DPOJET:BURSTConfig:CSACTIve {L | H}
DPOJET:BURSTConfig:CSACTIve?
Inputs
{L | H}
Outputs
{L | H}
DPOJET:BURSTConfig:CSSource
This command sets or queries the required source for Chip select.
Syntax
DPOJET:BURSTConfig:CSSource {CH1 — CH4 | MATH1 — MATH4 | REF1
— REF4}
DPOJET:BURSTConfig:CSSource?
338
Inputs
{CH1 — CH4 | MATH1 — MATH4 | REF1 — REF4}
Outputs
{CH1 — CH4 | MATH1 — MATH4 | REF1 — REF4}
DPOJET Printable Application Help
GPIB commands
DPOJET:BURSTConfig:CUSTOMRate
This command sets or queries the custom data rate values for a particular DDR
generation.
Syntax
DPOJET:BURSTConfig:CUSTOMRate <NR3>
DPOJET:BURSTConfig:CUSTOMRate?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:BURSTConfig:DATA
This command sets or queries the required source for Data.
Syntax
DPOJET:BURSTConfig:DATA {CH1 — CH4 | MATH1 — MATH4 | REF1 —
REF4}
DPOJET:BURSTConfig:DATA?
Inputs
{CH1 — CH4 | MATH1 — MATH4 | REF1 — REF4}
Outputs
{CH1 — CH4 | MATH1 — MATH4 | REF1 — REF4}
DPOJET Printable Application Help
339
GPIB commands
DPOJET:BURSTConfig:DATARate
This command sets or queries the standard data rate values for a particular DDR
generation.
Syntax
DPOJET:BURSTConfig:DATARate <string>
DPOJET:BURSTConfig:DATARate?
Inputs
<string>
Outputs
<string>
DPOJET:BURSTConfig:DETECTMethod
This command sets or queries the burst detection method used for burst
identification.
Syntax
DPOJET:BURSTConfig:DETECTMethod {DQDQS | CHIPSelect |
LOGICState}
DPOJET:BURSTConfig:DETECTMethod?
340
Inputs
{DQDQS | CHIPSelect | LOGICState}
Outputs
{DQDQS | CHIPSelect | LOGICState}
DPOJET Printable Application Help
GPIB commands
DPOJET:BURSTConfig:GENERation
This command sets or queries the required DDR generation.
Syntax
DPOJET:BURSTConfig:GENERation {DDR | DDR2 | DDR3 | LPDDR |
LPDDR2 | GDDR3 | GDDR5}
DPOJET:BURSTConfig:GENERation?
Inputs
{DDR | DDR2 | DDR3 | LPDDR | LPDDR2 | GDDR3 | GDDR5}
Outputs
{DDR | DDR2 | DDR3 | LPDDR | LPDDR2 | GDDR3 | GDDR5}
DPOJET:BURSTConfig:LATEncy
This command sets or queries the required burst latency.
Syntax
DPOJET:BURSTConfig:LATEncy <NR3>
DPOJET:BURSTConfig:LATEncy?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
341
GPIB commands
DPOJET:BURSTConfig:LENGth
This command sets or queries the required burst length.
Syntax
DPOJET:BURSTConfig:LENGth <NR3>
DPOJET:BURSTConfig:LENGth?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:BURSTConfig:SEARch
This command sets or queries the type of search required.
Syntax
DPOJET:BURSTConfig:SEARch {DDRRead | DDRWrite |
DDRREADWRITE}
DPOJET:BURSTConfig:SEARch?
342
Inputs
{DDRRead | DDRWrite | DDRREADWRITE}
Outputs
{DDRRead | DDRWrite | DDRREADWRITE}
DPOJET Printable Application Help
GPIB commands
DPOJET:BURSTConfig:STRObe
This command sets or queries the required source for the strobe.
Syntax
DPOJET:BURSTConfig:STRObe {CH1 - CH4 | MATH1 - MATH4 | REF1 REF4}
DPOJET:BURSTConfig:STRObe?
Inputs
{CH1 - CH4 | MATH1 - MATH4 | REF1 - REF4}
Outputs
{CH1 - CH4 | MATH1 - MATH4 | REF1 - REF4}
DPOJET:BURSTConfig:TOLERance
This command sets or queries the required burst tolerance.
Syntax
DPOJET:BURSTConfig:TOLERance
DPOJET:BURSTConfig:TOLERance?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
343
GPIB commands
DPOJET:CLEARALLMeas
This set-only command clears the entire current list of defined measurements in
DPOJET.
Syntax
Outputs
DPOJET:CLEARALLMeas
None
DPOJET:DESKEW
This command performs a DPOJET deskew operation with the settings specified
in DPOJET:DESKEW.
Syntax
DPOJET:DESKEW {EXEcute}
Inputs
{EXEcute}
DPOJET:DESKEW:DESKEWchannel
This command sets or queries the channel to be deskewed.
Syntax
DPOJET:DESKEW:DESKEWchannel {CH1-CH4}
DPOJET:DESKEW:DESKEWchannel?
Inputs
344
{CH1 - CH4}
DPOJET Printable Application Help
GPIB commands
Outputs
{CH1 - CH4}
DPOJET:DESKEW:DESKEWHysteresis
This command sets or queries the deskew channel hysteresis value.
Syntax
DPOJET:DESKEW:DESKEWHysteresis <NR3>
DPOJET:DESKEW:DESKEWHysteresis?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:DESKEW:DESKEWMidlevel
This command sets or queries the deskew channel midlevel value.
Syntax
DPOJET:DESKEW:DESKEWMidlevel <NR3>
DPOJET:DESKEW:DESKEWMidlevel?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
345
GPIB commands
DPOJET:DESKEW:EDGE
This command sets or queries the edge types used when calculating deskew.
Syntax
DPOJET:DESKEW:EDGE {RISE | FALL | BOTH}
DPOJET:DESKEW:EDGE?
Inputs
{RISE | FALL | BOTH}
Outputs
{RISE | FALL | BOTH}
DPOJET:DESKEW:MAXimum
This command sets or queries the maximum deskew value possible.
Syntax
DPOJET:DESKEW:MAXimum <NR3>
DPOJET:DESKEW:MAXimum?
346
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:DESKEW:MINimum
This command sets or queries the minimum deskew value possible.
Syntax
DPOJET:DESKEW:MINimum <NR3>
DPOJET:DESKEW:MINimum?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:DESKEW:REFChannel
This command sets or queries the reference channel used for deskew operation.
Syntax
DPOJET:DESKEW:REFChannel {CH1 - CH4}
DPOJET:DESKEW:REFChannel?
Inputs
{CH1 - CH4}
Outputs
{CH1 - CH4}
DPOJET Printable Application Help
347
GPIB commands
DPOJET:DESKEW:REFHysteresis
This command sets or queries the reference channel hysteresis value.
Syntax
DPOJET:DESKEW:REFHysteresis <NR3>
DPOJET:DESKEW:REFHysteresis?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:DESKEW:REFMidlevel
This command sets or queries the reference channel midlevel value.
Syntax
DPOJET:DESKEW:REFMidlevel <NR3>
DPOJET:DESKEW:REFMidlevel?
348
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:DIRacmodel
This command sets or queries the current dirac model.
Syntax
DPOJET:DIRacmodel {FIBREchannel | PCIExpress}
DPOJET:DIRacmodel?
Inputs
{FIBREchannel | PCIExpress}
Outputs
{FIBREchannel | PCIExpress}
DPOJET:EXPORT
This set-only command saves the specified DPOJET plot to the specified file
path. The Format is determined through the filename extension, with a default of
png if no extension is specified.
Supported extensions include jpeg, jpg, tif, tiff, bmp, emf, and png. For example:
DPOJET:EXPORT PLOT1, “savedimage.tif”.
Syntax
DPOJET:EXPORT {PLOT1-PLOT4, <file string>}
Inputs
{PLOT1-PLOT4, <file string>}
DPOJET Printable Application Help
349
GPIB commands
DPOJET:GATING
This command sets or queries the gating state.
Syntax
DPOJET:GATING {OFF | ZOOM | CURSOR | MARKS}
DPOJET:GATING?
Inputs
{OFF | ZOOM | CURSOR | MARKS}
Outputs
{OFF | ZOOM | CURSOR | MARKS}
DPOJET:HALTFreerunonlimfail
This command sets or queries the halt free-run on limit failure (On or Off).
Syntax
DPOJET:HALTFreerunonlimfail {1 | 0}
DPOJET:HALTFreerunonlimfail?
350
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:HIGHPerfrendering
This command sets or queries the current high-performance eye rendering
setting.
Syntax
DPOJET:HIGHPerfrendering <NR1>
DPOJET:HIGHPerfrendering?
Inputs
<NR1>
Outputs
<NR1>
DPOJET:INTERp
This command sets or queries the current interpolation model.
Syntax
DPOJET:INTERp {LINear | SINX}
DPOJET:INTERp?
Inputs
{LINear | SINX}
Outputs
{LINear | SINX}
DPOJET Printable Application Help
351
GPIB commands
DPOJET:JITtermode?
This command queries the current jitter mode.
Syntax
Outputs
DPOJET:JITtermode?
<string>
DPOJET:JITtermodel
This command sets the current jitter model.
Syntax
DPOJET:JITtermodel {BUJ | Legacy}
Inputs
{BUJ | Legacy}
DPOJET:ANALYSISMETHOD
This command sets or queries the current analysis method value.
Syntax
DPOJET:ANALYSISMETHOD { JITTEROnly | JITTERNoise }
DPOJET:ANALYSISMETHOD?
Inputs
352
JITTEROnly | JITTERNoise
DPOJET Printable Application Help
GPIB commands
DPOJET:LASTError?
This query-only command returns the contents of the last pop-up warning dialog
box. If no errors have occurred since startup, or since the last call to
DPOJET:LASTError?, this command returns an empty string.
Syntax
Outputs
DPOJET:LASTError?
<string>
DPOJET:LIMITRise
This command turns on or off the ability to limit Rise/Fall measurements to
transition bits only.
Syntax
DPOJET:LIMITRise {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
353
GPIB commands
DPOJET:MINBUJUI
This command sets or queries the minimum number of UI for BUJ analysis.
Syntax
DPOJET:MINBUJUI <NR3>
DPOJET:MINBUJUI?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:LIMits:FILEName
This command sets or queries the current limits filename.
Syntax
DPOJET:LIMits:FILEName <string>
DPOJET:LIMits:FILEName?
354
Inputs
<string>
Outputs
<string>
DPOJET Printable Application Help
GPIB commands
DPOJET:LIMits:STATE
This command turns on or off the pass-fail limit system. Pass-fail status can be
queried using the DPOJET:MEAS <x>:RESULTS node.
Syntax
DPOJET:LIMits:STATE {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:LOGging:MEASurements:FOLDer
This command sets or queries the current folder used for measurement logging.
Syntax
DPOJET:LOGging:MEASurements:FOLDer <string>
DPOJET:LOGging:MEASurements:FOLDer?
Inputs
<string>
Outputs
<string>
DPOJET Printable Application Help
355
GPIB commands
DPOJET:LOGging:MEASurements:STATE
This command turns on or off the future logging of measurements. Individual
measurements included in the logging are selected using the
DPOJET:MEAS<x>:LOGging node. This parameter turns on or off the entire set
of included measurements.
Syntax
DPOJET:LOGging:MEASurements: {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:LOGging:SNAPshot
This command performs a DPOJET export of the specified type, either for
statistics or measurements.
356
Syntax
DPOJET:LOGging:SNAPshot {STATistics | MEASurements}
Inputs
{STATistics | MEASurements}
Outputs
{STATistics | MEASurements}
DPOJET Printable Application Help
GPIB commands
DPOJET:LOGging:STATistics:FILEName
This command sets or queries the current file used for statistics logging.
Syntax
DPOJET:LOGging:STATistics:FILEName <string>
DPOJET:LOGging:STATistics:FILEName?
Inputs
<string>
Outputs
<string>
DPOJET:LOGging:STATistics:STATE
This command turns on or off the future logging of statistics. Individual
measurements included in the logging are selected using the
DPOJET:MEAS<x>:LOGging node. This parameter turns on or off the entire set
of included measurements.
Syntax
DPOJET:LOGging:STATistics:STATE {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
357
GPIB commands
DPOJET:LOGging:WORSTcase:FOLDer
This command sets or queries the current folder used for worst case logging.
NOTE. Waveform filenames generated while worst case logging is on will follow
the syntax of “Measurement Name”-“Source”_Min1.wfm and “Measurement
Name”-“Source”_Max1.wfm, For example: Period1-Ch1_Max1.wfm, Period1Ch1_Min1.wfm, Rise Time1-Ch1_Max1.wfm, Rise Time1-Ch1_Min1.wfm.
Syntax
DPOJET:LOGging:WORSTcase:FOLDer <string>
DPOJET:LOGging:WORSTcase:FOLDer?
Inputs
<string>
Outputs
<string>
DPOJET:LOGging:WORSTcase:STATE
This command turns on or off the future logging of worst case waveforms.
Individual measurements included in the logging are selected using the
DPOJET:MEAS<x>:LOGging node. This parameter turns on or off the entire set
of included measurements.
358
Syntax
DPOJET:LOGging:WORSTcase:STATE {1 | 0}
Inputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
Outputs
{1 | 0}
DPOJET:MEAS<x>
This command returns the branch query for the application measurement slot
with index <x>. This will always match the measurement defined at the
associated index <x> displayed on the DPOJET screen, where index 1 is the first,
or top, of the measurement list.
Branch queries will only contain the measurement branches for those branches
that have measurements defined. This means queries to branches that do not exist
will time out. This is required because the number of measurements that can be
defined in DPOJET, is 99.
Syntax
DPOJET:MEAS<x>
DPOJET:MEAS<x>?
DPOJET:MEAS<x>:BER:TARGETBER
This command sets or queries the BER value.
Syntax
DPOJET:MEAS<x>:BER:TARGETBER <NR3>
DPOJET:MEAS<x>:BER:TARGETBER?
Inputs
<NR3>
Outputs
<NR3>
NOTE. This command is different from DPOJET:MEAS:RJDJ:BER whose
configuration parameter exist in RJDJ tab.
NOTE. This command is different from DPOJET:MEAS:RNDN:BER whose
configuration parameter exist in RNDN tab.
DPOJET Printable Application Help
359
GPIB commands
DPOJET:MEAS<x>:BITCfgmethod
This command sets or queries the measurement bit configure method.
Syntax
DPOJET:MEAS<x>:BITCfgmethod {MEAN | MODE}
DPOJET:MEAS<x>:BITCfgmethod?
Inputs
{MEAN | MODE}
Outputs
{MEAN | MODE}
DPOJET:MEAS<x>:BITPcnt
This command sets or queries the percentage value to be measured for the Bit
type selected.
Syntax
DPOJET:MEAS<x>:BITPcnt <NR3>
DPOJET:MEAS<x>:BITPcnt?
360
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:BITConfig:STARTPercent
This command sets or queries the starting percentage of the bit to measure.
Syntax
DPOJET:MEAS<x>:BITConfig:STARTPercent <NR3>
DPOJET:MEAS<x>:BITConfig:STARTPercent?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:BITConfig:ENDPercent
This command sets or queries the ending percentage of the bit to measure.
Syntax
DPOJET:MEAS<x>:BITConfig:ENDPercent <NR3>
DPOJET:MEAS<x>:BITConfig:ENDPercent?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
361
GPIB commands
DPOJET:MEAS<x>:BITConfig:NUMBins
This command sets or queries the number of bins per window.
Syntax
DPOJET:MEAS<x>:BITConfig:NUMBins <NR3>
DPOJET:MEAS<x>:BITConfig:NUMBins?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:BITType
This command sets or queries the measurement bit type setting.
Syntax
DPOJET:MEAS<x>:BITType {ALLBits | NONTRANsition | TRANsition}
DPOJET:MEAS<x>:BITType?
362
Inputs
{ALLBits | NONTRANsition | TRANsition}
Outputs
{ALLBits | NONTRANsition | TRANsition}
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:BUSState:CLOCKPolarity
This command sets or queries the clock polarity for the clock edge.
Syntax
DPOJET:MEAS<x>:BUSState:CLOCKPolarity {RISING | FALLING}
DPOJET:MEAS<x>:BUSState:CLOCKPolarity?
Inputs
Outputs
{RISING | FALLING}
{RISing | FALLing}
DPOJET:MEAS<x>:BUSState:FROMPattern
This command sets or queries the Pattern from which the Bus state is configured.
Syntax
DPOJET:MEAS<x>:BUSState:FROMPattern <string>
DPOJET:MEAS<x>:BUSState:FROMPattern?
Inputs
<string>
Outputs
<string>
DPOJET Printable Application Help
363
GPIB commands
DPOJET:MEAS<x>:BUSState:FROMSymbol
This command sets or queries the symbol from which the Bus state is configured.
Syntax
DPOJET:MEAS<x>:BUSState:FROMSymbol <string>
DPOJET:MEAS<x>:BUSState:FROMSymbol?
Inputs
<string>
Outputs
<string>
DPOJET:MEAS<x>:BUSState:MEASUREType
This command sets or queries the type for which the bus state is configured.
Syntax
DPOJET:MEAS<x>:BUSState:MEASBUSType {SYMbol | PATTern}
DPOJET:MEAS<x>:BUSState:MEASBUSType?
364
Inputs
{SYMbol | PATTern}
Outputs
{SYMbol | PATTern}
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:BUSState:MEASUREFrom
This command sets or queries where the bus is measured from.
Syntax
DPOJET:MEAS<x>:BUSState:MEASUREFROM {CLOCKEdge | START |
STOP}
DPOJET:MEAS<x>:BUSState:MEASUREFROM?
Inputs
{CLOCKEdge | START | STOP}
Outputs
{CLOCKEdge | START | STOP}
DPOJET:MEAS<x>:BUSState:MEASURETO
This command sets or queries from where the bus is measured to.
Syntax
DPOJET:MEAS<x>:BUSState:MEASURETO {START | STOP | CLOCKEdge}
DPOJET:MEAS<x>:BUSState:MEASURETO?
Inputs
{CLOCKEdge | START | STOP}
Outputs
{CLOCKEdge | START | STOP}
DPOJET Printable Application Help
365
GPIB commands
DPOJET:MEAS<x>:BUSState:TOPattern
This command sets or queries the Pattern to which the Bus state is configured.
Syntax
DPOJET:MEAS<x>:BUSState: TOPattern <string>
DPOJET:MEAS<x>:BUSState: TOPattern?
Inputs
<string>
Outputs
<string>
DPOJET:MEAS<x>:BUSState:TOSymbol
This command sets or queries the symbol to which the Bus state is configured.
Syntax
DPOJET:MEAS<x>:BUSState: TOSymbol <string>
DPOJET:MEAS<x>:BUSState: TOSymbol?
366
Inputs
<string>
Outputs
<string>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKBitrate
This command sets or queries the clock bit rate. Used if DATARate is 1.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKBitrate <NR3>
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKBitrate?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKFrequency
This command sets or queries the clock frequency. Used with Constant Clock Fixed clock recovery method.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKFrequency <NR3>
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKFrequency?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
367
GPIB commands
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKMultiplier
This command sets or queries the clock multiplier.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKMultiplier <NR3>
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKMultiplier?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKPath
This command sets or queries the current known clock pattern path.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKPath <string>
DPOJET:MEAS<x>:CLOCKRecovery:CLOCKPath?
368
Inputs
<string>
Outputs
<string>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:CLOCKRecovery:DAMPing
This command sets or queries the clock recovery damping value.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:DAMPing <NR3>
DPOJET:MEAS<x>:CLOCKRecovery:DAMPing?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:CLOCKRecovery:DATARate
This command turns on or off DATArate usage.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:DATARate {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
369
GPIB commands
DPOJET:MEAS<x>:CLOCKRecovery:BWType
This command sets or queries the clock recovery bandwidth type.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:BWType {LOOPBW | JTFBW}
DPOJET:MEAS<x>:CLOCKRecovery:BWType?
Inputs
{LOOPBW | JTFBW}
Outputs
{LOOPBW | JTFBW}
DPOJET:MEAS<x>:CLOCKRecovery:LOOPBandwidth
This command sets or queries the clock recovery loop bandwidth.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:LOOPBandwidth <NR3>
DPOJET:MEAS<x>:CLOCKRecovery:LOOPBandwidth?
370
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:CLOCKRecovery:MEANAUTOCalculate
This command sets or queries how often the clock is calculated, either FIRST, or
on EVERY acquisition.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:MEANAUTOCalculate {FIRST |
EVERY}
DPOJET:MEAS<x>:CLOCKRecovery:MEANAUTOCalculate?
Inputs
{FIRST | EVERY}
Outputs
{FIRST | EVERY}
DPOJET:MEAS<x>:CLOCKRecovery:METHod
This command sets or queries the current Clock recovery method.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:METHod {STANDARD | CUSTOM |
CONSTMEAN | CONSTFIXED | EXPEDGE | EXPPLL | CONSTMEDIAN}
DPOJET:MEAS<x>:CLOCKRecovery:METHod?
Inputs
{STANDARD | CUSTOM | CONSTMEAN | CONSTFIXED | EXPEDGE |
EXPPLL | CONSTMEDIAN}
Outputs
{STANDARD | CUSTOM | CONSTMEAN | CONSTFIXED | EXPEDGE |
EXPPLL | CONSTMEDIAN}
DPOJET Printable Application Help
371
GPIB commands
DPOJET:MEAS<x>:CLOCKRecovery:MODel
This command sets or queries the current clock recovery model.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:MODel {ONE | TWO}
DPOJET:MEAS<x>:CLOCKRecovery:MODel?
Inputs
{ONE | TWO}
Outputs
{ONE | TWO}
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset
This command sets or queries the clock offset.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset <NR3>
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset?
372
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:AUTO?
This query-only command returns the value in the Auto text box for the Nominal
Clock Offset controls. If the nominal clock offset method selection type is set to
Auto and an acquisition cycle has been completed, this field shows the clock-todata offset that was automatically determined. A positive value means that the
clock leads the data (precedes it in time). If the offset has not been determined,
the returned string is TBD.
Syntax
Outputs
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:AUTO?
<string>
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:MANual
This command sets or queries the value for Manual text box.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:MANual <NR3>
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:MANual?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
373
GPIB commands
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:Recalctype
This command sets or queries the recalculation list box.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:Recalctype {FIRST |
EVERY}
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:Recalctype?
Inputs
{FIRST | EVERY}
Outputs
{FIRST | EVERY}
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:SELECTIONtype
This command sets or queries the selection type.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:SELECTIONtype
{AUTO | MANUAL}
DPOJET:MEAS<x>:CLOCKRecovery:NOMINALOFFset:SELECTIONtype?
374
Inputs
{AUTO | MANUAL}
Outputs
{AUTO | MANUAL}
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:CLOCKRecovery:PATTern
This command turns on or off the usage of CLOCKPath to a specific known data
pattern.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:PATTern {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:MEAS<x>:CLOCKRecovery:STAndard
This command sets or queries the current clock recovery standard, as specified in
the user interface.
Syntax
DPOJET:MEAS<x>:CLOCKRecovery:STAndard <string>
DPOJET:MEAS<x>:CLOCKRecovery:STAndard?
Inputs
<string>
Outputs
<string>
DPOJET Printable Application Help
375
GPIB commands
DPOJET:MEAS<x>:COMMONMode:FILTers:STATE
This command sets or queries the state of the common mode filter frequency.
Syntax
DPOJET:MEAS<x>:COMMONMode:FILTers:STATE {ON | OFF}
DPOJET:MEAS<x>:COMMONMode:FILTers:STATE?
Inputs
Outputs
{ON | OFF}
{1 | 0}
DPOJET:MEAS<x>:CUSTomname
This command sets or queries the custom measurement name for the
measurement in slot x.
Syntax
DPOJET:MEAS<x>:CUSTomname <string>
DPOJET:MEAS<x>:CUSTomname?
376
Inputs
<string>
Outputs
<string>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:DATA?
This query-only command returns the measurement data. This is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For Example: If <yyy>=500, <x>=3
NOTE. <x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
DPOJET:MEAS<x>:DATA?
The measurement values as a stream of doubles.
DPOJET:MEAS<x>:DDR:MPERCycle
This command sets or queries the MPercycle value used in various DDR
measurements.
Syntax
DPOJET:MEAS<x>:DDR:MPERCycle <NR3>
DPOJET:MEAS34:DDR:MPERCycle?
Inputs
<NR3>
DPOJET Printable Application Help
377
GPIB commands
Outputs
<NR1>
DPOJET:MEAS<x>:DDR:NPERCycle
This command sets or queries the NPercycle value used in various DDR
measurements.
Syntax
DPOJET:MEAS<x>:DDR:NPERCycle <NR3>
DPOJET:MEAS34:DDR:NPERCycle?
Inputs
<NR3>
Outputs
<NR1>
DPOJET:MEAS<x>:DDR:WINDowsize
This command sets or queries the window size used in various DDR
measurements.
Syntax
DPOJET:MEAS<x>:DDR:WINDowsize <NR3>
DPOJET:MEAS34:DDR:WINDowsize?
378
Inputs
<NR3>
Outputs
<NR1>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:EDGE1
This command sets or queries the Source1 edge type.
Syntax
DPOJET:MEAS<x>:EDGE1 {RISe | FALL | BOTH}
DPOJET:MEAS<x>:EDGE1?
Inputs
{RISe | FALL | BOTH}
Outputs
{RISe | FALL | BOTH}
DPOJET:MEAS<x>:EDGE2
This command sets or queries the Source2 edge type.
Syntax
DPOJET:MEAS<x>:EDGE2 {RISe | FALL | BOTH}
DPOJET:MEAS<x>:EDGE2?
Inputs
{RISe | FALL | BOTH}
Outputs
{RISe | FALL | BOTH}
DPOJET Printable Application Help
379
GPIB commands
DPOJET:MEAS<x>:EDGEIncre
This command sets or queries the measurement edge increment value.
Syntax
DPOJET:MEAS<x>:EDGEIncre <NR3>
DPOJET:MEAS<x>:EDGEIncre?
Inputs
<NR3>
Outputs
<NR1>
DPOJET:MEAS<x>:EDGES:FROMLevel
This command sets or queries the FromLevel edge for the measurement.
Syntax
DPOJET:MEAS<x>:EDGES:FROMLevel {HIGH | MID | LOW}
DPOJET:MEAS<x>:EDGES:FROMLevel?
380
Inputs
{HIGH | MID | LOW}
Outputs
{HIGH | MID | LOW}
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:EDGES:LEVel
This command sets or queries the level used for the edges configuration.
Syntax
DPOJET:MEAS<x>:EDGES:LEVel
DPOJET:MEAS<x>:EDGES:LEVel?
Inputs
{HIGH | MID | LOW}
Outputs
{HIGH | MID | LOW}
DPOJET:MEAS<x>:EDGES:SLEWRATETechnique
This command sets or queries the slew rate technique for the measurement.
Syntax
DPOJET:MEAS<x>:EDGES:SLEWRATETechnique {NOMinalmethod |
DDRmethod}
DPOJET:MEAS<x>:EDGES:SLEWRATETechnique?
Inputs
{NOMinalmethod | DDRmethod}
Outputs
{NOMinalmethod | DDRmethod}
DPOJET Printable Application Help
381
GPIB commands
DPOJET:MEAS<x>:EDGES:TOLevel
This command sets or queries the ToLevel edge for the measurement.
Syntax
DPOJET:MEAS<x>:EDGES:TOLevel {HIGH | MID | LOW}
DPOJET:MEAS<x>:EDGES:TOLevel?
Inputs
{HIGH | MID | LOW}
Outputs
{HIGH | MID | LOW}
DPOJET:MEAS<x>:FILTers:BLANKingtime
This command sets or queries the current filter blanking time.
Syntax
DPOJET:MEAS<x>:FILTers:BLANKingtime <NR3>
DPOJET:MEAS<x>:FILTers:BLANKingtime?
382
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:FILTers:HIGHPass:FREQ
This command sets or queries the current high pass filter frequency.
Syntax
DPOJET:MEAS<x>:FILTers:HIGHPass:FREQ <NR3>
DPOJET:MEAS<x>:FILTers:HIGHPass:FREQ?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:FILTers:HIGHPass:SPEC
This command sets or queries the current high pass filter specification.
Syntax
DPOJET:MEAS<x>:FILTers:HIGHPass:SPEC {NONE | FIRST | SECOND |
THIRD}
DPOJET:MEAS<x>:FILTers:HIGHPass:SPEC?
Inputs
{NONE | FIRST | SECOND | THIRD}
Outputs
{NONE | FIRST | SECOND | THIRD}
DPOJET Printable Application Help
383
GPIB commands
DPOJET:MEAS<x>:FILTers:LOWPass:FREQ
This command sets or queries the current low pass filter frequency.
Syntax
DPOJET:MEAS<x>:FILTers:LOWPass:FREQ <NR3>
DPOJET:MEAS<x>:FILTers:LOWPass:FREQ?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:FILTers:LOWPass:SPEC
This command sets or queries the current low pass filter specification.
Syntax
DPOJET:MEAS<x>:FILTers:LOWPass:SPEC {NONE | FIRST | SECOND |
THIRD}
DPOJET:MEAS<x>:FILTers:LOWPass:SPEC?
384
Inputs
{NONE | FIRST | SECOND | THIRD}
Outputs
{NONE | FIRST | SECOND | THIRD}
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:REFVoltage
This command sets or queries the reference voltage for the measurement.
Syntax
DPOJET:MEAS<x>:REFVoltage {100 | -100}
DPOJET:MEAS<x>:REFVoltage?
Inputs
{100 | -100}
Outputs
{100 | -100}
DPOJET:MEAS<x>:FILTers:RAMPtime
This command sets or queries the current filter ramp time.
Syntax
DPOJET:MEAS<x>:FILTers:RAMPtime <NR3>
DPOJET:MEAS<x>:FILTers:RAMPtime?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
385
GPIB commands
DPOJET:MEAS<x>:FROMedge
This command sets the FROMedge value for the measurement.
Syntax
DPOJET:MEAS<x>:FROMedge {RISe | FALL | BOTH}
Inputs
{RISe | FALL | BOTH}
Outputs
{RISe | FALL | BOTH}
DPOJET:MEAS<x>:HIGHREFVoltage
This command sets or queries the high reference voltage value for the selected
configuration.
Syntax
DPOJET:MEAS<x>:HIGHREFVoltage <NR3>
DPOJET:MEAS<x>:HIGHREFVoltage?
386
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:LOWREFVoltage
This command sets or queries the low reference voltage value for the selected
configuration.
Syntax
DPOJET:MEAS<x>:LOWREFVoltage <NR3>
DPOJET:MEAS<x>:LOWREFVoltage?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:LOGging:MEASurements:FILEname?
This command queries the current file name that will be used for the
measurement when measurement logging is turned on.
Syntax
Outputs
DPOJET:MEAS<x>:LOGging:MEASurements:FILEname?
<string>
DPOJET Printable Application Help
387
GPIB commands
DPOJET:MEAS<x>:LOGging:MEASurements:SELect
This command sets or queries the given measurement to be included in any
measurement logging. Statistic logging is turned on or off as a whole, using the
DPOJET:LOGging branch.
Syntax
DPOJET:MEAS<x>:LOGging:MEASurements:SELect {1 | 0}
DPOJET:MEAS<x>:LOGging:MEASurements:SELect?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:MEAS<x>:LOGging:STATistics:SELect
This command sets or queries the given measurement for inclusion in any
statistic logging. Statistic logging is turned on or off as a whole, using the
DPOJET:LOGging branch.
Syntax
DPOJET:MEAS<x>:LOGging:STATistics:SELect {1 | 0}
DPOJET:MEAS<x>:LOGging:STATistics:SELect?
388
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:LOGging:WORSTcase:SELect
This command sets or queries the given measurement for inclusion in any worstcase logging. Statistic logging is turned on or off as a whole, using the
DPOJET:LOGging branch.
Syntax
DPOJET:MEAS<x>:LOGging:WORSTcase:SELect {1 | 0}
Inputs
DPOJET:MEAS<x>:LOGging:WORSTcase:SELect?
{1 | 0}
Outputs
{1 | 0}
DPOJET:MEAS<x>:MASKfile
This command sets or queries the current mask file name.
Syntax
DPOJET:MEAS<x>:MASKfile <string>
DPOJET:MEAS<x>:MASKfile?
Inputs
<string>
Outputs
<string>
DPOJET Printable Application Help
389
GPIB commands
DPOJET:MEAS<x>:MASKOffset:HORIzontal:SELECTIONtype
This command sets or queries the selection type.
Syntax
DPOJET:MEAS<x>:MASKOffset:HORIzontal:SELECTIONtype { AUTOFIT |
MANUAL}
DPOJET:MEAS<x>:MASKOffset:HORIzontal:SELECTIONtype?
Inputs
{AUTOFIT | MANUAL}
Outputs
{AUTOFIT | MANUAL}
DPOJET:MEAS<x>:MASKOffset:HORIzontal:AUTOfit?
This query-only command returns the value in the Autofit text box for the Mask
Offset controls. If the mask offset method selection type is set to Autofit and an
acquisition cycle has been completed, this field shows the displacement of the
mask offset that was automatically determined. A positive value means that the
mask has moved to the right. If the offset has not been determined, the returned
string is TBD.
Syntax
Outputs
390
DPOJET:MEAS<x>:MASKOffset:HORIzontal:AUTOfit?
<string>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:MASKOffset:HORIzontal:MANual
This command sets or queries the value for Manual text box.
Syntax
DPOJET:MEAS<x>:MASKOffset:HORIzontal:MANual <NR3>
DPOJET:MEAS<x>:MASKOffset:HORIzontal:MANual?
Inputs
<NR3>
Outputs
<NR3>
MEAS<x>:MEASRange
DPOJET:MEAS<x>:MEASRange:MAX
This command sets or queries the maximum measurement range limit value.
Syntax
DPOJET:MEAS<x>:MEASRange:MAX <NR3>
DPOJET:MEAS<x>:MEASRange:MAX?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
391
GPIB commands
DPOJET:MEAS<x>:MEASRange:MIN
This command sets or queries the minimum measurement range limit value.
Syntax
DPOJET:MEAS<x>:MEASRange:MIN <NR3>
DPOJET:MEAS<x>:MEASRange:MIN?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:MEASRange:STATE
This command turns on or off the measurement range limits.
392
Syntax
DPOJET:MEAS<x>:MEASRange:STATE {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:MEASStart
This command sets or queries the measurement start value.
Syntax
DPOJET:MEAS<x>:MEASStart <NR3>
DPOJET:MEAS<x>:MEASStart?
Inputs
<NR3>
Outputs
<NR1>
DPOJET:MEAS<x>:N
This command sets or queries the measurement N value.
Syntax
DPOJET:MEAS<x>:N <NR3>
DPOJET:MEAS<x>:N?
Inputs
<NR3>
Outputs
<NR1>
DPOJET Printable Application Help
393
GPIB commands
DPOJET:MEAS<x>:NAME?
This query-only command returns the measurement name for the measurement in
slot x. For measurements that include 16-bit characters in their UI names, such as
DJDirac, the string returned will contain question marks where the UI contains
nontext characters.
Syntax
Outputs
DPOJET:MEAS<x>:NAME?
<string>
DPOJET:MEAS<x>:PHASENoise:HIGHLimit
This command sets or queries the upper phase noise integration limit.
Syntax
DPOJET:MEAS<x>:PHASENoise:HIGHLimit <NR3>
DPOJET:MEAS<x>:PHASENoise:HIGHLimit?
394
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:PHASENoise:LOWLimit
This command sets or queries the lower phase noise integration limit.
Syntax
DPOJET:MEAS<x>:PHASENoise:LOWLimit <NR3>
DPOJET:MEAS<x>:PHASENoise:LOWLimit?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:REFVoltage
This command sets or queries the reference voltage for the measurement.
Syntax
DPOJET:MEAS<x>:REFVoltage {100 | —100}
DPOJET:MEAS<x>:REFVoltage?
Inputs
{100 | —100}
Outputs
{100 | —100}
DPOJET Printable Application Help
395
GPIB commands
DPOJET:MEAS<x>:RESULts?
This query-only command returns the measurement branch for the currently
selected measurement for measurement slot <x>.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts?
The measurement branch for the selected measurement for measurement slot x.
DPOJET:MEAS<x>:RESULts:ALLAcqs?
This query-only command returns the measurement results from all acquisitions.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs?
<NR3>
DPOJET:MEAS<x>:RESULts:ALLAcqs:HITPopulation?
This query-only command returns the mask hit population.
Syntax
Outputs
396
DPOJET:MEAS<x>:RESULts:ALLAcqs:HITPopulation?
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:RESULts:ALLAcqs:HITS?
This query-only command returns the mask hits measurement for all segments.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:HITS?
<NR3>
DPOJET:MEAS<x>:RESULts:ALLacqs:LIMits:STATus?
This query-only command returns the pass/fail status per measurement. If any of
the statistics fails, the cumulative result is fail, otherwise pass.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLacqs:LIMits:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:ALLacqs:LIMits:HIgh:STATus?
This query-only command returns the pass/fail status for high limit.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLacqs:LIMits:HIgh:STATus?
{PASS | FAIL}
DPOJET Printable Application Help
397
GPIB commands
DPOJET:MEAS<x>:RESULts:ALLacqs:LIMits:LOw:STATus?
This query-only command returns the pass/fail status for low limit.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLacqs:LIMits:LOw:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAX?
This query-only command returns the maximum value for all accumulated
measurement acquisitions for slot <x>.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAX?
<NR3>
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAXCC?
This query-only command returns the maximum positive cycle-to-cycle delta of
the selected measurement.
Syntax
Outputs
398
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAXCC?
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAXCC:STATus?
This query-only command returns the pass/fail status for the maximum positive
cycle-to-cycle delta of the selected measurement (set
via :DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLacqs:MAXCC:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAXHits?
This query-only command returns the maximum mask hits measurement for all
segments.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAXHits?
<NR3>
DPOJET:MEAS<x>:RESULts:ALLAcqs:MAX:STATus?
This query-only command returns the pass/fail status for the max measurement
for the currently loaded limit file (set via :DPOJET:LIMits:FILEName).
Syntax
DPOJET:MEAS<x>:RESULts:ALLacqs:MAX:STATus?
DPOJET Printable Application Help
399
GPIB commands
Outputs
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:ALLAcqs:MEAN?
This query-only command returns the mean value for all accumulated
measurement acquisitions for slot <x>.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:MEAN?
<NR3>
DPOJET:MEAS<x>:RESULts:ALLAcqs:MEAN:STATus?
This query-only command returns the pass/fail status for the mean measurement
for the currently loaded limit file (set via :DPOJET:LIMits:FILEName).
Syntax
Outputs
400
DPOJET:MEAS<x>:RESULts:ALLAcqs:MEAN:STATus?
{PASS | FAIL}
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:RESULts:ALLAcqs:MIN?
This query-only command returns the minimum value for all accumulated
measurement acquisitions for slot <x>.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:MIN?
<NR3>
DPOJET:MEAS<x>:RESULts:ALLAcqs:MINCC?
This query-only command returns the maximum negative cycle-to-cycle delta of
the selected measurement.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:MINCC?
<NR3>
DPOJET:MEAS<x>:RESULts:ALLAcqs:MINCC:STATus?
This query-only command returns the pass/fail status for the negative cycle-tocycle delta of the selected measurement.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:MINCC:STATus?
{PASS | FAIL}
DPOJET Printable Application Help
401
GPIB commands
DPOJET:MEAS<x>:RESULts:ALLAcqs:MINHits?
This query-only command returns the minimum mask hits measurement for all
segments.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:MINHits?
<NR3>
DPOJET:MEAS<x>:RESULts:ALLAcqs:MIN:STATus?
This query-only command returns the pass/fail status for the minimum
measurement for the currently loaded limit file (set
via :DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:MIN:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:ALLacqs:PK2PK?
This query-only command returns the peak-to-peak value for all accumulated
measurement acquisitions for slot <x>.
Syntax
402
DPOJET:MEAS<x>:RESULts:ALLacqs:PK2PK?
DPOJET Printable Application Help
GPIB commands
Outputs
<NR3>
DPOJET:MEAS<x>:RESULts:ALLacqs:PK2PK:STATus?
This query-only command returns the pass/fail status for the peak-to-peak
measurement for the currently loaded limit file (set
via :DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLacqs:PK2PK:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:ALLAcqs:POPUlation?
This query-only command returns the mean measurement value for the currently
selected measurement for measurement slot <x>.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:POPUlation?
<NR1>
DPOJET Printable Application Help
403
GPIB commands
DPOJET:MEAS<x>:RESULts:ALLacqs:POPUlation:STATus?
This query-only command returns the pass/fail status for the population
measurement for the currently loaded limit file (set
via :DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLacqs:POPUlation:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:ALLAcqs:SEG(x):Hits?
This query-only command returns the mask hits measurement for the given
segment, either SEG1, SEG2 or SEG3.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:SEG<x>:Hits?
<NR3>
DPOJET:MEAS<x>:RESULts:ALLAcqs:SEG(x):MAXHits?
This query-only command returnseturns the maximum mask hits measurement
for the given segment, either SEG1, SEG2 or SEG3.
Syntax
404
DPOJET:MEAS<x>:RESULts:ALLAcqs:SEG<x>:MAXHits?
DPOJET Printable Application Help
GPIB commands
Outputs
<NR3>
DPOJET:MEAS<x>:RESULts:ALLAcqs:SEG(x):MINHits?
This query-only command returns the minimum mask hits measurement for the
given segment, either SEG1, SEG2 or SEG3.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:SEG<x>:MINHits?
<NR3>
DPOJET:MEAS<x>:RESULts:ALLAcqs:STDDev?
This query-only command returns the standard deviation for all accumulated
measurement acquisitions for slot <x>.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLAcqs:STDDev?
<NR3>
DPOJET Printable Application Help
405
GPIB commands
DPOJET:MEAS<x>:RESULts:ALLacqs:STDDEV:STATus?
This query-only command returns the pass/fail status for the standard deviation
measurement for the currently loaded limit file (set
via :DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:ALLacqs:STDDEV:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:CURRentacq:MAX?
This query-only command returns the maximum value of the measurement value
for the currently selected measurement for measurement slot <x>.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:MAX?
<NR3>
DPOJET:MEAS<x>:RESULts:CURRentacq:MAXCC?
This query-only command returns the maximum positive cycle-to-cycle delta of
the selected measurement.
Syntax
406
DPOJET:MEAS<x>:RESULts:CURRentacq:MAXCC?
DPOJET Printable Application Help
GPIB commands
Outputs
<NR3>
DPOJET:MEAS<x>:RESULts:CURRentacq:MAXCC:STATus?
This query-only command returns the pass/fail status for the Max cycle-to-cycle
measurement for the currently loaded limit file. (Set using
DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:MAXCC:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:CURRentacq:MAX:STATus?
This query-only command returns the pass/fail status for the max measurement
for the currently loaded limit file. (Set using DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:MAX:STATus?
{PASS | FAIL}
DPOJET Printable Application Help
407
GPIB commands
DPOJET:MEAS<x>:RESULts:CURRentacq:MEAN?
This query-only command returns the mean measurement for the currently loaded
limit file.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:MEAN?
<NR3>
DPOJET:MEAS<x>:RESULts:CURRentacq:MEAN:STATus?
This query-only command returns the pass/fail status for the mean measurement
for the currently loaded limit file. (Set using DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:MEAN:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:CURRentacq:MIN?
This query-only command returns the minimum value for the currently selected
measurement for measurement slot <x>.
Syntax
Outputs
408
DPOJET:MEAS<x>:RESULts:CURRentacq:MIN?
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:RESULts:CURRentacq:MINCC?
This query-only command returns the maximum negative cycle-to-cycle delta of
the selected measurement.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:MINCC?
<NR3>
DPOJET:MEAS<x>:RESULts:CURRentacq:MINCC:STATus?
This query-only command returns the pass/fail status for the min cycle-to-cycle
measurement for the currently loaded limit file. (Set using
DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:MINCC:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:CURRentacq:MIN:STATus?
This query-only command returns the pass/fail status for the minimum
measurement for the currently loaded limit file. (Set using
DPOJET:LIMits:FILEName).
Syntax
DPOJET:MEAS<x>:RESULts:CURRentacq:MIN:STATus?
DPOJET Printable Application Help
409
GPIB commands
Outputs
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:CURRentacq:PK2PK?
This query-only command returns the peak-to-peak value for the currently
selected measurement for measurement slot <x>.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:PK2PK?
<NR3>
DPOJET:MEAS<x>:RESULts:CURRentacq:PK2PK:STATus?
This query-only command returns the pass/fail status for the peak-to-peak
measurement for the currently loaded limit file. (Set using
DPOJET:LIMits:FILEName).
Syntax
Outputs
410
DPOJET:MEAS<x>:RESULts:CURRentacq:PK2PK:STATus?
{PASS | FAIL}
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:RESULts:CURRentacq:POPUlation?
This query-only command returns the population measurement value for the
currently selected measurement for measurement slot <x>.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:POPUlation?
<NR1>
DPOJET:MEAS<x>:RESULts:CURRentacq:POPUlation:STATus?
This query-only command returns the pass/fail status for the population
measurement for the currently loaded limit file. (Set using
DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:POPUlation:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULts:CURRentacq:STDDev?
This query-only command returns the standard deviation of the measurement
value for the currently selected measurement for measurement slot <x>.
Syntax
DPOJET:MEAS<x>:RESULts:CURRentacq:StdDev?
DPOJET Printable Application Help
411
GPIB commands
Outputs
<NR3>
DPOJET:MEAS<x>:RESULts:CURRentacq:STDDev:STATus?
This query-only command returns the pass/fail status for the standard deviation
measurement for the currently loaded limit file. (Set using
DPOJET:LIMits:FILEName).
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:CURRentacq:STDDev:STATus?
{PASS | FAIL}
DPOJET:MEAS<x>:RESULTS:STATus?
This query-only command returns the status of the given measurement values in
slot MEAS<x>. Valid for currently valid measurements, or the error status such
as “Not enough edges”.
Syntax
Outputs
412
DPOJET:MEAS<x>:RESULTS:STATus?
<string>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:RESULts:VIew?
This query-only command returns the results view type.
Syntax
Outputs
DPOJET:MEAS<x>:RESULts:VIew?
{SUMmary | DETails}
DPOJET:MEAS<x>:RJDJ:BER
This command sets or queries the RJDJ Target BER value.
Syntax
DPOJET:MEAS<x>:RJDJ:BER <NR3>
DPOJET:MEAS<x>:RJDJ:BER?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
413
GPIB commands
DPOJET:MEAS<x>:RJDJ:DETECTPLEN
This command sets or queries the current detect plan.
Syntax
DPOJET:MEAS<x>:RJDJ:DETECTPLEN {0 | 1 | ON | OFF}
Inputs
<NR3>
0 is Manual
1 is Auto
Outputs
<NR3>
DPOJET:MEAS<x>:RJDJ:PATLen
This command sets or queries the current RJDJ pattern length.
Syntax
DPOJET:MEAS<x>:RJDJ:PATLen <NR3>
DPOJET:MEAS<x>:RJDJ:PATLen?
414
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:RJDJ:TYPe
This command sets or queries the current RJDJ measurement type.
Syntax
DPOJET:MEAS<x>:RJDJ:TYPe {ARBITrary | REPEating}
DPOJET:MEAS<x>:RJDJ:TYPe?
Inputs
{ARBitrary | REPEating}
Outputs
{ARBitrary | REPEating}
DPOJET:MEAS<x>:RJDJ:WINDOwlength
This command sets or queries the current RJDJ window length.
Syntax
DPOJET:MEAS<x>:RJDJ:WINDOwlength <NR3>
DPOJET:MEAS<x>:RJDJ:WINDOwlength?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
415
GPIB commands
DPOJET:MEAS<x>:RNDN:BER
This command sets or queries the RNDN Target BER value.
Syntax
DPOJET:MEAS<x>:RNDN:BER <NR3>
DPOJET:MEAS<x>:RNDN:BER?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:RNDN:AUTODETECTpattern
This command sets or queries the current detect plan.
Syntax
DPOJET:MEAS(x):RNDN:AUTODETECTpattern {1 | 0 | ON | OFF}
Inputs
<NR3>
0 is Manual
1 is Auto
416
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:RNDN:PATLen
This command sets or queries the current RNDN pattern length.
Syntax
DPOJET:MEAS<x>:RNDN:PATLen <NR3>
DPOJET:MEAS<x>:RNDN:PATLen?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:RNDN:TYPe
This command sets or queries the current RNDN measurement type.
Syntax
DPOJET:MEAS<x>:RNDN:TYPe {ARBITrary | REPEating}
DPOJET:MEAS<x>:RNDN:TYPe?
Inputs
{ARBitrary | REPEating}
Outputs
{ARBitrary | REPEating}
DPOJET Printable Application Help
417
GPIB commands
DPOJET:MEAS<x>:RNDN:WINDOwlength
This command sets or queries the current RNDN window length.
Syntax
DPOJET:MEAS<x>:RNDN:WINDOwlength <NR3>
DPOJET:MEAS<x>:RNDN:WINDOwlength?
Inputs
<NR3>
Outputs
<NR3>
DPOJET:MEAS<x>:SIGNALType
This command sets the signal type for various measurements.
418
Syntax
DPOJET:MEAS<x>:SIGNALType {CLOCK | DATA | AUTO}
Inputs
{CLOCK | DATA | AUTO}
Outputs
{CLOCK | DATA | AUTO}
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:SOUrce1
This command sets or queries the Source1 value.
Syntax
DPOJET:MEAS<x>:SOUrce1 {CH1 - CH4 | MATH1 - MATH4 | REF1 - REF4 |
D0 — D15}
DPOJET:MEAS<x>:SOUrce1?
Inputs
{CH1 - CH4 | MATH1 - MATH4 | REF1 - REF4 | D0 — D15}
Outputs
{CH1 - CH4 | MATH1 - MATH4 | REF1 - REF4 | D0 — D15}
DPOJET:MEAS<x>:SOUrce2
This command sets or queries the Source2 value. May return NONE for singlesource measurement. Source2 may be the second source used in dual-source
measurements, or the clock source in others. In either case, it is always the same
as the rightmost displayed source on the UI.
Syntax
DPOJET:MEAS<x>:SOUrce2 {CH1 - CH4 | MATH1 - MATH4 | REF1 - REF4 |
D0 — D15}
DPOJET:MEAS<x>:SOUrce2?
Inputs
{CH1 - CH4 | MATH1 - MATH4 | REF1 - REF4 | D0 — D15}
Outputs
{CH1 - CH4 | MATH1 - MATH4 | REF1 - REF4 | D0 — D15}
DPOJET Printable Application Help
419
GPIB commands
DPOJET:MEAS<x>:SSC:NOMinalfreq:AUTO?
This query-only command returns the automatically-calculated nominal
frequency value for SSC configurations.
Syntax
Outputs
DPOJET:MEAS<x>:SSC:NOMinalfreq:AUTO?
<string>
DPOJET:MEAS<x>:SSC:NOMinalfreq:MANual
This command sets or queries the user-defined nominal frequency value for SSC
configurations.
Syntax
DPOJET:MEAS<x>:SSC:NOMinalfreq:MANual <NR3>
DPOJET:MEAS<x>:SSC:NOMinalfreq:MANual?
420
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:MEAS<x>:SSC:NOMinalfreq:SELECTIONtype
This command sets or queries the Nominal frequency selection type for the SSC
configurations.
Syntax
DPOJET:MEAS<x>:SSC:NOMinalfreq:SELECTIONtype
DPOJET:MEAS<x>:SSC:NOMinalfreq:SELECTIONtype?
Inputs
{AUTO | MANUAL}
Outputs
{AUTO | MANUAL}
DPOJET:MEAS<x>:TIMEDATa?
This query-only command returns the measurement time data. It is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For Example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
DPOJET:MEAS<x>:TIMEDATa?
DPOJET Printable Application Help
421
GPIB commands
Outputs
After parsing the query results, the data is a stream of doubles.
NOTE. Time data is not available for all measurements. For Example: Scalar
measurements.
DPOJET:MEAS<x>:TOEdge
This command sets the TOEdge value for the measurement.
Syntax
DPOJET:MEAS<x>:TOEdge {SAMEas | OPPositeas}
Inputs
{SAMEas | OPPositeas}
Outputs
{SAMEas | OPPositeas}
DPOJET:MEAS<x>:ZOOMEVENT
This command zooms into the waveform where a max/min value occurs in a
measurement.
422
Syntax
DPOJET:MEAS<x>:ZOOMEVENT {"MAX" | "MIN"}
Inputs
{"MAX" | "MIN"}
DPOJET Printable Application Help
GPIB commands
DPOJET:NUMMeas?
This query-only command returns the current number of defined measurements.
Syntax
Outputs
DPOJET:NUMMeas?
<NR1>
DPOJET:ADDPlot
This set-only command creates a plot of the specified type on the specified
DPOJET measurement. Up to four plots can be created.
Syntax
DPOJET:ADDPlot {TIMEtrend | DATAarray | HISTOgram | SPECtrum |
TRANSfer | PHASEnoise | EYE | WAVEform | BATHtub | QBathtub |
QPulsewidth | COMPOSITEJitterhist | NOISEBAthtub | BERContour} |
CORRELATEDEye |PDFEye | BEREye | COMPOSITENoisehist | MEAS<x>}
Inputs
{TIMEtrend | DATAarray | HISTOgram | SPECtrum | TRANSfer | PHASEnoise |
EYE | WAVEform | BATHtub | QBathtub | QPulsewidth | COMPOSITEJitterhist
| NOISEBAthtub | BERContour} | CORRELATEDEye |PDFEye | BEREye |
COMPOSITENoisehist | MEAS<x>}
For example: DPOJET:ADDPlot HISTOgram, MEAS2
DPOJET Printable Application Help
423
GPIB commands
DPOJET:CLEARALLPlots
This set-only command clears the entire current list of defined plots in DPOJET.
Syntax
DPOJET:CLEARALLPlots
DPOJET:PLOT<x>:COMPOSITEJitterhist:VERTical:SCALE
This command sets or queries the vertical scale setting for applicable plots, either
Linear or Log.
NOTE. Undefined for non-composite jitter histogram plots.
Syntax
DPOJET:PLOT<x>:COMPOSITEJitterhist:VERTical:SCALE {LINEAR |
LOG}
DPOJET:PLOT<x>:COMPOSITEJitterhist:VERTical:SCALE?
424
Inputs
{LINEAR | LOG}
Outputs
{LINEAR | LOG}
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:COMPOSITEJitterhist:NUMBins
This command sets or queries the current composite jitter histogram resolution.
NOTE. Undefined for non-composite jitter histogram plots.
Syntax
DPOJET:PLOT<x>:COMPOSITEJitterhist:NUMBins {TWENtyfive | FIFTY |
HUNdred | TWOFifty | FIVEHundred | TWOThousand | MAXimum}
DPOJET:PLOT<x>:COMPOSITEJitterhist:NUMBins?
Inputs
Outputs
{TWENtyfive | FIFTY | HUNdred | TWOFifty | FIVEHundred| TWOThousand |
MAXimum}
TWENtyfive | FIFTY | HUNdred | TWOFifty | FIVEHundred| TWOThousand |
MAXimum}
DPOJET:PLOT<x>:COMPOSITEJitterhist:TJ
This command sets or queries the TJ Jitter component settings.
NOTE. Undefined for non-composite jitter histogram plots.
Syntax
DPOJET:PLOT<x>:COMPOSITEJitterhist:TJ {1 | 0}
DPOJET:PLOT<x>:COMPOSITEJitterhist:TJ?
Inputs
{1 | 0}
DPOJET Printable Application Help
425
GPIB commands
Outputs
{1 | 0}
DPOJET:PLOT<x>:COMPOSITEJitterhist:RJNPJ
This command sets or queries the RJ+NPJ Jitter component settings.
NOTE. Undefined for non-composite jitter histogram plots.
Syntax
DPOJET:PLOT<x>:COMPOSITEJitterhist:RJNPJ {1 | 0}
DPOJET:PLOT<x>:COMPOSITEJitterhist:RJNPJ?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:COMPOSITEJitterhist:PJ
This command sets or queries the PJ Jitter component settings.
NOTE. Undefined for non-composite jitter histogram plots.
Syntax
DPOJET:PLOT<x>:COMPOSITEJitterhist:PJ {1 | 0}
DPOJET:PLOT<x>:COMPOSITEJitterhist:PJ?
Inputs
426
{1 | 0}
DPOJET Printable Application Help
GPIB commands
Outputs
{1 | 0}
DPOJET:PLOT<x>:COMPOSITEJitterhist:DDJDCD
This command sets or queries the DDJ+DCD Jitter component settings.
NOTE. Undefined for non-composite jitter histogram plots.
Syntax
DPOJET:PLOT<x>:COMPOSITEJitterhist:DDJDCD {1 | 0}
DPOJET:PLOT<x>:COMPOSITEJitterhist:DDJDCD?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:DATA:XDATa?
This command returns the plot X data values. This command is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
DPOJET Printable Application Help
427
GPIB commands
Syntax
Outputs
DPOJET:PLOT<x>:DATA:XDATa?
After parsing the query results, the data is a stream of doubles.
NOTE. This command does not support plots such as the Eye Diagram Height
plot, Waveform Plot and Eye diagram with mask hits.
DPOJET:PLOT<x>:DATA:XDATa:TJ?
This command returns the TJ plot X data values. This command is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
428
DPOJET:PLOT<x>:DATA:XDATa:TJ?
After parsing the query results, the data is a stream of doubles.
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:DATA:XDATa:RJBUJ?
This command returns the RJ+BUJ plot X data values. This command is similar
to the curve query, where the output is in the format
#<x><yyy><data><newline>, where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of <y> bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
DPOJET:PLOT<x>:DATA:XDATa:RJBUJ?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:XDATa:PJ?
This command returns the PJ plot X data values. This command is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of <y> bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
DPOJET Printable Application Help
429
GPIB commands
Syntax
Outputs
DPOJET:PLOTx:DATA:XDATa:PJ?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:XDATa:DDJDCD?
This command returns the DDJ+DCD plot X data values. This command is
similar to the curve query, where the output is in the format
#<x><yyy><data><newline>, where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of <y> bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
430
DPOJET:PLOT<x>:DATA:XDATa:DDJDCD?
After parsing the query results, the data is a stream of doubles.
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:DATA:XDATa:TN
This command returns the TN plot X data values. This command is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
DPOJET:PLOT<x>:DATA:XDATa:TN?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:XDATa:RNNPN
This command returns the RNNPN plot X data values. This command is similar
to the curve query, where the output is in the format
#<x><yyy><data><newline>, where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
DPOJET:PLOT<x>:DATA:XDATa:RNNPN?
DPOJET Printable Application Help
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GPIB commands
Outputs
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:XDATa:PN
This command returns the PN plot X data values. This command is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
DPOJET:PLOT<x>:DATA:XDATa:PN?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:XDATa:DDNZERO
This command returns the DDNZERO plot X data values. This command is
similar to the curve query, where the output is in the format
#<x><yyy><data><newline>, where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
432
DPOJET Printable Application Help
GPIB commands
Syntax
Outputs
DPOJET:PLOT<x>:DATA:XDATa:DDNZERO?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:XDATa:DDNONE
This command returns the DDNONE plot X data values. This command is
similar to the curve query, where the output is in the format
#<x><yyy><data><newline>, where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
DPOJET:PLOT<x>:DATA:XDATa:DDNONE?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:YDATa?
This command returns the plot Y data values. This command is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
DPOJET Printable Application Help
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GPIB commands
Syntax
Outputs
DPOJET:PLOT<x>:DATA:XDATa?
After parsing the query results, the data is a stream of doubles.
NOTE. This command does not support plots such as the Eye Diagram Height
plot, Waveform Plot and Eye diagram with mask hits.
DPOJET:PLOT<x>:DATA:YDATa:TJ?
This command returns the TJ plot Y data values. This command is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
434
DPOJET:PLOT<x>:DATA:YDATa:TJ?
After parsing the query results, the data is a stream of doubles.
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:DATA:YDATa:RJBUJ?
This command returns the RJ+BUJ plot Y data values. This command is similar
to the curve query, where the output is in the format
#<x><yyy><data><newline>, where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of <y> bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
DPOJET:PLOT<x>:DATA:YDATa:RJBUJ?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:YDATa:PJ?
This command returns the PJ plot Y data values. This command is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of <y> bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
DPOJET Printable Application Help
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GPIB commands
Syntax
Outputs
DPOJET:PLOT<x>:DATA:YDATa:PJ?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:YDATa:DDJDCD?
This command returns the DDJ+DCD plot Y data values. This command is
similar to the curve query, where the output is in the format
#<x><yyy><data><newline>, where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of <y> bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
436
DPOJET:PLOT<x>:DATA:YDATa:DDJDCD?
After parsing the query results, the data is a stream of doubles.
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:DATA:YDATa:TN
This command returns the TN plot Y data values. This command is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
DPOJET:PLOT<x>:DATA:YDATa:TN?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:YDATa:RNNPN
This command returns the RNNPN plot Y data values. This command is similar
to the curve query, where the output is in the format
#<x><yyy><data><newline>, where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
DPOJET Printable Application Help
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GPIB commands
Syntax
Outputs
DPOJET:PLOT<x>:DATA:YDATa:RNNPN?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:YDATa:PN
This command returns the PN plot Y data values. This command is similar to the
curve query, where the output is in the format #<x><yyy><data><newline>,
where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
438
DPOJET:PLOT<x>:DATA:YDATa:PN?
After parsing the query results, the data is a stream of doubles.
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:DATA:YDATa:DDNONE
This command returns the DDNONE plot Y data values. This command is
similar to the curve query, where the output is in the format
#<x><yyy><data><newline>, where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
Syntax
Outputs
DPOJET:PLOT<x>:DATA:YDATa:DDNONE?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:DATA:YDATa:DDNZERO
This command returns the DDNZERO plot Y data values. This command is
similar to the curve query, where the output is in the format
#<x><yyy><data><newline>, where <x> is the number of <y> bytes.
For example: If <yyy>=500, <x>=3
<x> is hexadecimal format. The letters A-F denote the number of y bytes
between 10 and 15 digits.
<yyy> is the number of bytes to transfer.
<data> is curve data.
<newline> is a single-byte new line character at the end of the data.
DPOJET Printable Application Help
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GPIB commands
Syntax
Outputs
DPOJET:PLOT<x>:DATA:YDATa:DDNZERO?
After parsing the query results, the data is a stream of doubles.
DPOJET:PLOT<x>:XUnits?
This query-only command returns X units of the plot as a string.
Syntax
Outputs
DPOJET:PLOT<x>:XUnits?
<string>
NOTE. Plot units depends on the measurement type.Click here to see the possible
DPOJET:PLOT<x>:YUnits?
This query-only command returns Y units of the plot as a string.
Syntax
Outputs
DPOJET:PLOT<x>:YUnits?
<string>
NOTE. Plot units depends on the measurement type.Click here to see the possible
440
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:SOUrce?
This query-only command returns the source measurement for the selected plot.
Syntax
Outputs
DPOJET:PLOT<x>:SOUrce?
{MEAS1 - MEAS99}
DPOJET:PLOT<x>:TREND:TYPe
This command sets or queries the trend type setting for Trend plots.
Syntax
DPOJET:PLOT<x>:TREND:TYPe {VECTOR | BAR}
DPOJET:PLOT<x>:TREND:TYPe?
Inputs
{VECTOR | BAR}
Outputs
{VECTOR | BAR}
DPOJET Printable Application Help
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GPIB commands
DPOJET:PLOT<x>:TYPe?
This query-only command returns the current plot type for the selected plot.
Syntax
Outputs
DPOJET:PLOT<x>:TYPe?
{TIMEtrend | DATAarray | HISTOgram | SPECtrum | TRANSfer | PHASEnoise |
EYE | WAVEform | BATHtub | QBathtub | QPulsewidth | COMPOSITEJitterhist
| NOISEBAthtub | BERContour} | CORRELATEDEye |PDFEye | BEREye |
COMPOSITENoisehist }
DPOJET:PLOT<x>:BATHtub:BER
This command sets or queries the bathtub BER value.
Syntax
DPOJET:PLOT<x>:BATHtub:BER <NR3>
DPOJET:PLOT<x>:BATHtub:BER?
Inputs
<NR3>
Outputs
<NR1>
NOTE. Undefined for nonbathtub plots.
442
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:BATHtub:VERTical:SCALE
This command sets or queries the vertical scale setting for applicable plots, either
Linear or Log.
Syntax
DPOJET:PLOT<x>:BATHtub:VERTical:SCALE {LINEAR | LOG}
DPOJET:PLOT<x>:BATHtub:VERTical:SCALE?
Inputs
{LINEAR | LOG}
Outputs
{LINEAR | LOG}
NOTE. Undefined for nonbathtub plots.
DPOJET:PLOT<x>:EYE:ALIGNment
This command sets or queries eye alignment state for eye plots.
Syntax
DPOJET:PLOT<x>:EYE:ALIGNment {AUTO | LEFT | CENter}
DPOJET:PLOT<x>:EYE:ALIGNment?
Inputs
{AUTO | LEFT | CENter}
Outputs
{AUTO | LEFT | CENter}
NOTE. Undefined for noneye plots.
DPOJET Printable Application Help
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GPIB commands
DPOJET:PLOT<x>:EYE:HORizontal:AUTOscale
This command sets or queries the horizontal auto scale setting.
Syntax
DPOJET:PLOT<x>:EYE:HORizontal:AUTOscale {1 | 0}
DPOJET:PLOT<x>:EYE:HORizontal:AUTOscale?
Inputs
{1 | 0}
Outputs
{1 | 0}
NOTE. Undefined for noneye plots.
DPOJET:PLOT<x>:EYE:HORizontal:RESolution
This command sets or queries the Horizontal Eye resolution.
Syntax
DPOJET:PLOT<x>:EYE:HORizontal:RESolution <NR3>
DPOJET:PLOT<x>:EYE:HORizontal:RESolution?
Inputs
<NR3>
Outputs
<NR1>
NOTE. Undefined for noneye plots.
444
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:EYE:MASKfile
This command sets or queries the mask file.
Syntax
DPOJET:PLOT<x>:EYE:MASKfile <string>
DPOJET:PLOT<x>:EYE:MASKfile?
Inputs
<string>
Outputs
<string>
NOTE. Undefined for noneye plots.
DPOJET:PLOT<x>:EYE:STATE
This command sets or queries the eye state, either on or off.
Syntax
DPOJET:PLOT<x>:EYE:STATE {1 | 0}
DPOJET:PLOT<x>:EYE:STATE?
Inputs
{1 | 0}
Outputs
{1 | 0}
NOTE. Undefined for noneye plots.
DPOJET Printable Application Help
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GPIB commands
DPOJET:PLOT<x>:EYE:SUPERImpose
This command sets or queries whether superimposed eyes are generated in eye
diagrams.
Syntax
DPOJET:PLOT<x>:EYE:SUPERImpose {1 | 0}
DPOJET:PLOT<x>:EYE:SUPERImpose?
Inputs
{1 | 0}
Outputs
{1 | 0}
NOTE. Undefined for noneye plots.
DPOJET:PLOT<x>:HISTOgram:AUTOset
This command runs a histogram autoset for the specified slot.
Syntax
DPOJET:PLOT<x>:HISTOgram:AUTOset {EXECute}
Inputs
{EXECute}
NOTE. Undefined for nonhistogram plots.
446
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:HISTOgram:HORizontal:AUTOscale
This command sets or queries the horizontal auto scale settings.
Syntax
DPOJET:PLOT<x>:HISTOgram:HORizontal:AUTOscale {1 | 0}
DPOJET:PLOT<x>:HISTOgram:HORizontal:AUTOscale?
Inputs
{1 | 0}
Outputs
{1 | 0}
NOTE. Undefined for nonhistogram plots.
DPOJET:PLOT<x>:HISTOgram:HORizontal:CENter
This command sets or queries the histogram center.
Syntax
DPOJET:PLOT<x>:HISTOgram:HORizontal:CENter <NR3>
DPOJET:PLOT<x>:HISTOgram:HORizontal:CENter?
Inputs
<NR3>
Outputs
<NR3>
NOTE. Undefined for nonhistogram plots.
DPOJET Printable Application Help
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GPIB commands
DPOJET:PLOT<x>:HISTOgram:HORizontal:SPAN
This command sets or queries the histogram span.
Syntax
DPOJET:PLOT<x>:HISTOgram:HORizontal:SPAN <NR3>
DPOJET:PLOT<x>:HISTOgram:HORizontal:SPAN?
Inputs
<NR3>
Outputs
<NR3>
NOTE. Undefined for nonhistogram plots.
DPOJET:PLOT<x>:HISTOgram:NUMBins
This command sets or queries the current histogram resolution.
Syntax
DPOJET:PLOT<x>:HISTOgram:NUMBins {TWENtyfive | FIFTY | HUNdred |
TWOFifty | FIVEHundred | TWOThousand | MAXimum}
DPOJET:PLOT<x>:HISTOgram:NUMBins?
Inputs
{TWENtyfive | FIFTY | HUNdred | TWOFifty | FIVEHundred | TWOThousand |
MAXimum}
Outputs
{TWENtyfive | FIFTY | HUNdred | TWOFifty | FIVEHundred | TWOThousand |
MAXimum}
NOTE. Undefined for nonhistogram plots.
448
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:HISTOgram:VERTical:SCALE
This command sets or queries the vertical scale setting for applicable plots, either
Linear or Log.
Syntax
DPOJET:PLOT<x>:HISTOgram:VERTical:SCALE {LINEAR | LOG}
DPOJET:PLOT<x>:HISTOgram:VERTical:SCALE?
Inputs
{LINEAR | LOG}
Outputs
{LINEAR | LOG}
NOTE. Undefined for nonhistogram plots.
DPOJET:PLOT<x>:PHASEnoise:BASEline
This command sets or queries the phase noise baseline.
Syntax
DPOJET:PLOT<x>:PHASEnoise:BASEline <NR3>
DPOJET:PLOT<x>:PHASEnoise:BASEline?
Inputs
<NR3>
Outputs
<NR1>
NOTE. Undefined for nonphase-noise plots.
DPOJET Printable Application Help
449
GPIB commands
DPOJET:PLOT<x>:SPECtrum:BASE
This command sets or queries the spectrum base. Undefined for non-spectrum
plots.
Syntax
DPOJET:PLOT<x>:SPECtrum:BASE <NR3>
DPOJET:PLOT<x>:SPECtrum:BASE?
Inputs
<NR3>
Outputs
<NR1>
DPOJET:PLOT<x>:SPECtrum:HORizontal:SCALE
This command sets or queries the horizontal scale setting for applicable plots,
either Linear or Log.
Syntax
DPOJET:PLOT<x>:SPECtrum:HORizontal:SCALE {LINEAR | LOG}
DPOJET:PLOT<x>:SPECtrum:HORizontal:SCALE?
Inputs
{LINEAR | LOG}
Outputs
{LINEAR | LOG}
NOTE. Undefined for nonspectrum plots.
450
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:SPECtrum:MODE
This command sets or queries the spectrum mode.
Syntax
DPOJET:PLOT<x>:SPECtrum:MODE {NORMal | AVErage | PEAKhold}
DPOJET:PLOT<x>:SPECtrum:MODE?
Inputs
{NORMal | AVErage | PEAKhold}
Outputs
{NORMal | AVErage | PEAKhold}
DPOJET:PLOT<x>:SPECtrum:VERTical:SCALE
This command sets or queries the vertical scale setting for applicable plots, either
Linear or Log.
Syntax
DPOJET:PLOT<x>:SPECtrum:VERTical:SCALE {LINEAR | LOG}
DPOJET:PLOT<x>:SPECtrum:VERTical:SCALE?
Inputs
{LINEAR | LOG}
Outputs
{LINEAR | LOG}
NOTE. Undefined for nonspectrum plots.
DPOJET Printable Application Help
451
GPIB commands
DPOJET:PLOT<x>:TRANSfer:DENominator
This command sets or queries the transfer plot denominator.
Syntax
DPOJET:PLOT<x>:TRANSfer:DENominator {MEAS1 - MEAS99}
DPOJET:PLOT<x>:TRANSfer:DENominator?
Inputs
{MEAS1 - MEAS99}
Outputs
{MEAS1 - MEAS99}
NOTE. Undefined for non-transfer plots.
DPOJET:PLOT<x>:TRANSfer:HORizontal:SCALE
This command sets or queries the horizontal scale setting for applicable plots,
either Linear or Log. Undefined for nontransfer plots.
Syntax
DPOJET:PLOT<x>:TRANSfer:HORizontal:SCALE {LINEAR | LOG}
DPOJET:PLOT<x>:TRANSfer:HORizontal:SCALE?
452
Inputs
{LINEAR | LOG}
Outputs
{LINEAR | LOG}
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:TRANSfer:MODE
This command sets or queries the transfer plot mode.
Syntax
DPOJET:PLOT<x>:TRANSfer:MODE {NORMal | AVErage}
DPOJET:PLOT<x>:TRANSfer:MODE?
Inputs
{NORMal | AVErage}
Outputs
{NORMal | AVErage}
DPOJET:PLOT<x>:TRANSfer:NUMerator
This command sets or queries the transfer plot numerator.
Syntax
DPOJET:PLOT<x>:TRANSfer:NUMerator {MEAS1 - MEAS99}
DPOJET:PLOT<x>:TRANSfer:NUMerator?
Inputs
{MEAS1 - MEAS99}
Outputs
{MEAS1 - MEAS99}
NOTE. Undefined for nontransfer plots.
DPOJET Printable Application Help
453
GPIB commands
DPOJET:PLOT<x>:TRANSfer:VERTical:SCALE
This command sets or queries the vertical scale setting for applicable plots, either
Linear or Log. Undefined for non-transfer plots.
Syntax
DPOJET:PLOT<x>:TRANSfer:VERTical:SCALE {LINEAR | LOG}
DPOJET:PLOT<x>:TRANSfer:VERTical:SCALE?
Inputs
{LINEAR | LOG}
Outputs
{LINEAR | LOG}
DPOJET:PLOT<x>:BERContour:ALIGNment
This command sets or queries the BER contour alighment.
Syntax
DPOJET:PLOT<x>:BERContour:ALIGNment {AUTO | LEFT | CENter}
DPOJET:PLOT<x>:BERContour:ALIGNment?
Inputs
{AUTO | LEFT | CENter}
Outputs
{AUTO | LEFT | CENter}
454
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:BERContour:HORizontal:AUTOscale
This command sets or queries the horizontal auto scale setting.
Syntax
DPOJET:PLOT<x>:BERContour:HORizontal:AUTOscale {1 | 0}
DPOJET:PLOT<x>:BERContour:HORizontal:AUTOscale?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:BERContour:HORizontal:RESolution
This command sets or queries the Horizontal Eye resolution.
Syntax
DPOJET:PLOT<x>:BERContour:HORizontal:RESolution <NR3>
DPOJET:PLOT<x>:BERContour:HORizontal:RESolution?
Inputs
<NR3>
DPOJET:PLOT<x>:BERContour:MASK
This command sets or queries the eye state, either on or off.
Syntax
DPOJET:PLOT<x>:BERContour:MASK {1 | 0}
DPOJET:PLOT<x>:BERContour:MASK?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
455
GPIB commands
DPOJET:PLOT<x>:BERContour:MASKFile
This command sets or queries the mask file.
Syntax
DPOJET:PLOT<x>:BERContour:MASKFile <string>
DPOJET:PLOT<x>:BERContour:MASKFile?
Inputs
<string>
Outputs
<string>
DPOJET:PLOT<x>:BERContour:SUPERImpose
This command sets or queries whether superimposed eyes are generated in eye
diagrams.
Syntax
DPOJET:PLOT<x>:BERContour:SUPERImpose {1 | 0}
DPOJET:PLOT<x>:BERContour:SUPERImpose?
Inputs
{1 | 0}
Outputs
{1 | 0}
456
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:BERContour:BER1E6V
This command sets or queries the BER1E6 Contour display.
Syntax
DPOJET:PLOT<x>:BERContour:BER1E6V {1 | 0}
DPOJET:PLOT<x>:BERContour:BER1E6V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:BERContour:BER1E9V
This command sets or queries the BER1E9 Contour display.
Syntax
DPOJET:PLOT<x>:BERContour:BER1E9V {1 | 0}
DPOJET:PLOT<x>:BERContour:BER1E9V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
457
GPIB commands
DPOJET:PLOT<x>:BERContour:BER1E12V
This command sets or queries the BER1E12 Contour display.
Syntax
DPOJET:PLOT<x>:BERContour:BER1E12V {1 | 0}
DPOJET:PLOT<x>:BERContour:BER1E12V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:BERContour:BER1E15V
This command sets or queries the BER1E15 Contour display.
Syntax
DPOJET:PLOT<x>:BERContour:BER1E15V {1 | 0}
DPOJET:PLOT<x>:BERContour:BER1E15V?
458
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:BERContour:BER1E18V
This command sets or queries the BER1E18 Contour display.
Syntax
DPOJET:PLOT<x>:BERContour:BER1E18V {1 | 0}
DPOJET:PLOT<x>:BERContour:BER1E18V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:BERContour:TARGETBER
This command sets or queries the Target BER Contour display.
Syntax
DPOJET:PLOT<x>:BERContour:TARGETBER{1 | 0}
DPOJET:PLOT<x>:BERContour:TARGETBER?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
459
GPIB commands
DPOJET:PLOT<x>:VERTBATHtub:BER
This command sets or queries the noise bathtub BER value.
Syntax
DPOJET:PLOT<x>:VERTBATHtub:BER <NR3>
DPOJET:PLOT<x>:VERTBATHtub:BER?
Inputs
<NR3>
Outputs
<NR1>
DPOJET:PLOT<x>:VERTBATHtub:HORIzontal:SCALE
This command sets or queries the horizontal scale setting for applicable plots,
either Linear or Log.
Syntax
DPOJET:PLOT<x>:VERTBATHtub:HORIzontal:SCALE {LINEAR | LOG}
DPOJET:PLOT<x>:VERTBATHtub:HORIzontal:SCALE?
Inputs
{LINEAR | LOG}
Outputs
{LINEAR | LOG}
460
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:CORRELATEDEye:BER1E6V
This command sets or queries the BER1E6 Contour display.
Syntax
DPOJET:PLOT<x>:CORRELATEDEye:BER1E6V {1 | 0}
DPOJET:PLOT<x>:CORRELATEDEye:BER1E6V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:CORRELATEDEye:BER1E9V
This command sets or queries the BER1E9 Contour display.
Syntax
DPOJET:PLOT<x>:CORRELATEDEye:BER1E9V {1 | 0}
DPOJET:PLOT<x>:CORRELATEDEye:BER1E9V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
461
GPIB commands
DPOJET:PLOT<x>:CORRELATEDEye:BER1E12V
This command sets or queries the BER1E12 Contour display.
Syntax
DPOJET:PLOT<x>:CORRELATEDEye:BER1E12V {1 | 0}
DPOJET:PLOT<x>:CORRELATEDEye: BER1E12V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:CORRELATEDEye:BER1E15V
This command sets or queries the BER1E15 Contour display.
Syntax
DPOJET:PLOT<x>:CORRELATEDEye:BER1E15V {1 | 0}
DPOJET:PLOT<x>:CORRELATEDEye:BER1E15V?
462
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:CORRELATEDEye:BER1E18V
This command sets or queries the BER1E18 Contour display.
Syntax
DPOJET:PLOT<x>:CORRELATEDEye:BER1E18V {1 | 0}
DPOJET:PLOT<x>:CORRELATEDEye:BER1E18V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:CORRELATEDEye:TARGETBER
This command sets or queries the TARGETBER Contour display.
Syntax
DPOJET:PLOT<x>:CORRELATEDEye:TARGETBER {1 | 0}
DPOJET:PLOT<x>:CORRELATEDEye:TARGETBER?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
463
GPIB commands
DPOJET:PLOT<x>:PDFEye:BER1E6V
This command sets or queries the BER1E6 Contour display.
Syntax
DPOJET:PLOT<x>:PDFEye:BER1E6V {1 | 0}
DPOJET:PLOT<x>:PDFEye:BER1E6V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:PDFEye:BER1E9V
This command sets or queries the BER1E9 Contour display.
Syntax
DPOJET:PLOT<x>:PDFEye: BER1E9V {1 | 0}
DPOJET:PLOT<x>:PDFEye: BER1E9V?
464
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:PDFEye:BER1E12V
This command sets or queries the BER1E12 Contour display.
Syntax
DPOJET:PLOT<x>:PDFEye:BER1E12V {1 | 0}
DPOJET:PLOT<x>:PDFEye:BER1E12V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:PDFEye:BER1E15V
This command sets or queries the BER1E15 Contour display.
Syntax
DPOJET:PLOT<x>:PDFEye:BER1E15V {1 | 0}
DPOJET:PLOT<x>:PDFEye:BER1E15V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
465
GPIB commands
DPOJET:PLOT<x>:PDFEye:BER1E18V
This command sets or queries the BER1E18 Contour display.
Syntax
DPOJET:PLOT<x>:PDFEye:BER1E18V {1 | 0}
DPOJET:PLOT<x>:PDFEye:BER1E18V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:PDFEye:TARGETBER
This command sets or queries the TARGETBER Contour display.
Syntax
DPOJET:PLOT<x>: PDFEye:TARGETBER {1 | 0}
DPOJET:PLOT<x>: PDFEye:TARGETBER?
466
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:BEREye:BER1E6V
This command sets or queries the BER1E6 Contour display.
Syntax
DPOJET:PLOT<x>:BEREye:BER1E6V {1 | 0}
DPOJET:PLOT<x>:BEREye:BER1E6V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:BEREye:BER1E9V
This command sets or queries the BER1E9 Contour display.
Syntax
DPOJET:PLOT<x>:BEREye:BER1E9V {1 | 0}
DPOJET:PLOT<x>:BEREye:BER1E9V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
467
GPIB commands
DPOJET:PLOT<x>:BEREye:BER1E12V
This command sets or queries the BER1E12 Contour display.
Syntax
DPOJET:PLOT<x>:BEREye:BER1E12V {1 | 0}
DPOJET:PLOT<x>:BEREye:BER1E12V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:BEREye:BER1E15V
This command sets or queries the BER1E15 Contour display.
Syntax
DPOJET:PLOT<x>:BEREye:BER1E15V {1 | 0}
DPOJET:PLOT<x>:BEREye:BER1E15V?
468
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:BEREye:BER1E18V
This command sets or queries the BER1E18 Contour display.
Syntax
DPOJET:PLOT<x>:BEREye:BER1E18V {1 | 0}
DPOJET:PLOT<x>:BEREye:BER1E18V?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:BEREye:TARGETBER
This command sets or queries the TARGETBER Contour display.
Syntax
DPOJET:PLOT<x>:BEREye:TARGETBER {1 | 0}
DPOJET:PLOT<x>:BEREye:TARGETBER?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
469
GPIB commands
DPOJET:PLOT<x>:COMPOSITENoisehist:HORIzontal:SCALE
This command sets or queries the Horizontal scale setting for applicable plots,
either Linear or Log.
Syntax
DPOJET:PLOT<x>:COMPOSITENoisehist:HORIzontal:SCALE {LINEAR |
LOG}
DPOJET:PLOT<x>:COMPOSITENoisehist:HORIzontal:SCALE?
Inputs
{LINEAR | LOG}
Outputs
{LINEAR | LOG}
DPOJET:PLOT<x>:COMPOSITENoisehist:NUMBins
This command sets or queries the current composite noise histogram resolution.
Syntax
DPOJET:PLOT<x>:COMPOSITENoisehist:NUMBins { TWENtyfive | FIFTY |
HUNdred | TWOFifty | FIVEHundred | TWOThousand | MAXimum}
DPOJET:PLOT<x>:COMPOSITENoisehist:NUMBins?
470
Inputs
{ TWENtyfive | FIFTY | HUNdred | TWOFifty | FIVEHundred | TWOThousand |
MAXimum}
Outputs
{ TWENtyfive | FIFTY | HUNdred | TWOFifty | FIVEHundred | TWOThousand |
MAXimum}
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:COMPOSITENoisehist:TN
This command sets or queries the TN Noise component settings.
Syntax
DPOJET:PLOT<x>:COMPOSITENoisehist:TN {1 | 0}
DPOJET:PLOT<x>:COMPOSITENoisehist:TN?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:COMPOSITENoisehist:RNNPN
This command sets or queries the RN+NPN Noise component settings.
Syntax
DPOJET:PLOT<x>:COMPOSITENoisehist:RNNPN {1 | 0}
DPOJET:PLOT<x>:COMPOSITENoisehist:RNNPN?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
471
GPIB commands
DPOJET:PLOT<x>:COMPOSITENoisehist:PN
This command sets or queries the PN Noise component settings.
Syntax
DPOJET:PLOT<x>:COMPOSITENoisehist:PN {1 | 0}
DPOJET:PLOT<x>:COMPOSITENoisehist:PN?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:PLOT<x>:COMPOSITENoisehist:DDNZERO
This command sets or queries the DDN(0) Noise component settings.
Syntax
DPOJET:PLOT<x>:COMPOSITENoisehist:DDNZERO {1 | 0}
DPOJET:PLOT<x>:COMPOSITENoisehist:DDNZERO?
472
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT<x>:COMPOSITENoisehist:DDNONE
This command sets or queries the DDN(1) Noise component settings.
Syntax
DPOJET:PLOT<x>:COMPOSITENoisehist:DDNONE {1 | 0}
DPOJET:PLOT<x>:COMPOSITENoisehist:DDNONE?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:POPULATION:CONDition
This command sets or queries the current population limit condition.
Syntax
DPOJET:POPULATION:CONDition {EACHmeas | LASTmeas}
DPOJET:POPULATION:CONDition?
Inputs
{EACHmeas | LASTmeas}
Outputs
{EACHmeas | LASTmeas}
DPOJET Printable Application Help
473
GPIB commands
DPOJET:POPULATION:LIMIT
This command sets or queries the current limit value.
Syntax
DPOJET:POPULATION:LIMIT <NR3>
DPOJET:POPULATION:LIMIT?
Inputs
<NR3>
Outputs
<NR1>
DPOJET:POPULATION:LIMITBY
This command sets or queries the mechanism by limits, either acquisition or
population.
Syntax
DPOJET:POPULATION:LIMITBY {ACQuisitions | POPUlation}
DPOJET:POPULATION:LIMITBY?
474
Inputs
{ACQuisitions | POPUlation}
Outputs
{ACQuisitions | POPUlation}
DPOJET Printable Application Help
GPIB commands
DPOJET:POPULATION:STATE
This command turns on or off population limits.
Syntax
DPOJET:POPULATION:STATE {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:QUALify:ACTIVE
This command sets the active state for the qualifier source, either HIGH or LOW.
Syntax
DPOJET:QUALify:ACTIVE {HIGH | LOW}
Inputs
{HIGH | LOW}
Outputs
{HIGH | LOW}
DPOJET Printable Application Help
475
GPIB commands
DPOJET:QUALify:SOUrce
This command sets the qualifier source.
Syntax
DPOJET:QUALify:SOUrce {CH1 – CH4 | MATH1 - MATH4 | REF1 - REF4 |
SEARCH0 – SEARCH8}
Inputs
{CH1 – CH4 | MATH1 - MATH4 | REF1 - REF4 | SEARCH0 – SEARCH8}
Outputs
{CH1 – CH4 | MATH1 - MATH4 | REF1 - REF4 | SEARCH0 – SEARCH8}
DPOJET:QUALify:STATE
This command turns on or off measurement qualification.
476
Syntax
DPOJET:QUALify:STATE {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:REFLevel:CH<x>:MIDZero
This command turns on or off the mid reference level voltage setting.
Syntax
DPOJET:REFLevel:CH<x>:MIDZero {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:REFLevels:AUTOSet
This command performs a DPOJET ref level autoset on any sources selected
using DPOJET:REFLevels:CH<x>:AUTOSet.
Syntax
DPOJET:REFLevels:AUTOSet {EXECute}
Inputs
{EXECute}
NOTE. All pieces of the reflevel branch have the ability to set ref levels for CH1CH4, MATH1-MATH4, and REF1-Ref4. Only the CH<x> portion is shown in
this OLH, but it exists and matches exactly for MATH
(DPOJET:REFLevels:MATH<x> and REF (DPOJET:REFLevels:REF<x>).
DPOJET Printable Application Help
477
GPIB commands
DPOJET:REFLevels:AUTOset:STATE?
This query-only command provides the Ref Level Autoset status.
Syntax
Outputs
DPOJET:REFLevels:AUTOset:STATE?
RUNNING | STOPPED
DPOJET:REFLevels:CH<x>:AUTOSet
This command sets or clears the reflevel autoset state of the given source. When
set to 1, the given source will have a ref level autoset acted on it during the next
acquisition.
Syntax
DPOJET:REFLevels:CH<x>:AUTOSet {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
NOTE. The Ref Level Autoset state is shown only for Ch1-Ch4 sources. It is the
same for MATH and Ref waveforms. For example: DPOJET:REFLevels:
MATH<x>, DPOJET:REFLevels:REF<x>.
478
DPOJET Printable Application Help
GPIB commands
DPOJET:REFLevels:CH<x>:ABsolute
The ABSolute branch specifies the ref levels in cases where a user chooses not to
run a ref level autoset on a given source. If a user does run a ref level autoset, the
percentage values of Rise, Fall and Hysteresis are used.
DPOJET:REFLevels:CH<x>:ABsolute:RISEHigh
This command sets the ref level voltage relative to base top for autoset. The
default is 1.0.
Syntax
DPOJET:REFLevels:CH<x>:ABsolute:RISEHigh <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET:REFLevels:CH<x>:ABsolute:RISELow
This command sets the ref level voltage relative to base top for autoset. The
default is -1.0.
Syntax
DPOJET:REFLevels:CH<x>:ABsolute:RISELow <NR3>
Inputs
<NR3>
DPOJET Printable Application Help
479
GPIB commands
Outputs
<NR3>
DPOJET:REFLevels:CH<x>:ABsolute:RISEMid
This command sets the ref level voltage relative to base top for autoset. The
default is 0.0.
Syntax
DPOJET:REFLevels:CH<x>:ABsolute:RISEMid <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET:REFLevels:CH<x>:ABsolute:FALLHigh
This command sets the ref level voltage relative to base top for autoset. The
default is 1.0.
480
Syntax
DPOJET:REFLevels:CH<x>:ABsolute:FALLHigh <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:REFLevels:CH<x>:ABsolute:FALLLow
This command sets the ref level voltage relative to base top for autoset. The
default is -1.1.
Syntax
DPOJET:REFLevels:CH<x>:ABsolute:FALLLow <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET:REFLevels:CH<x>:ABsolute:FALLMid
This command sets the ref level voltage relative to base top for autoset. The
default is 0.0.
Syntax
DPOJET:REFLevels:CH<x>:ABsolute:FALLMid <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
481
GPIB commands
DPOJET:REFLevels:CH<x>:ABsolute:HYSTeresis
This command sets the hysteresis value used for autoset. The default is 0.03.
Syntax
DPOJET:REFLevels:CH<x>:ABsolute:HYSTeresis <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET:REFLevels:CH<x>:BASETop
This command sets the base-top method for autoset.
482
Syntax
DPOJET:REFLevels:CH<x>:BASETop {MINMax | FULLhistogram |
EYEhistogram | AUTO}
Inputs
{MINMax | FULLhistogram | EYEhistogram | AUTO}
Outputs
{MINMax | FULLhistogram | EYEhistogram | AUTO}
DPOJET Printable Application Help
GPIB commands
DPOJET:REFLevels:CH<x>:PERcent
The ref level commands that follow set percent ref level parameters in the same
way that the absolute parameters do, except that these commands set the various
percentage levels used by the autoset.
DPOJET:REFLevels:CH<x>:PERcent:FALLHigh
This command sets the ref level voltage relative to base top for autoset.
Syntax
DPOJET:REFLevels:CH<x>:PERcent:FALLHigh <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET:REFLevels:CH<x>:PERcent:FALLLow
This command sets the ref level voltage relative to base top for autoset.
Syntax
DPOJET:REFLevels:CH<x>:PERcent:FALLLow <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
483
GPIB commands
DPOJET:REFLevels:CH<x>:PERcent:FALLMid
This command sets the ref level voltage relative to base top for autoset.
Syntax
DPOJET:REFLevels:CH<x>:PERcent:FALLMid <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET:REFLevels:CH<x>:PERcent:HYSTeresis
This command sets the hysteresis value used for autoset.
484
Syntax
DPOJET:REFLevels:CH<x>:PERcent:HYSTeresis <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
GPIB commands
DPOJET:REFLevels:CH<x>:PERcent:RISEHigh
This command sets the ref level voltage relative to base top for autoset.
Syntax
DPOJET:REFLevels:CH<x>:PERcent:RISEHigh <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET:REFLevels:CH<x>:PERcent:RISELow
This command sets the ref level voltage relative to base top for autoset.
Syntax
DPOJET:REFLevels:CH<x>:PERcent:RISELow <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
485
GPIB commands
DPOJET:REFLevels:CH<x>:PERcent:RISEMid
This command sets the ref level voltage relative to base top for autoset.
Syntax
DPOJET:REFLevels:CH<x>:PERcent:RISEMid <NR3>
Inputs
<NR3>
Outputs
<NR3>
DPOJET:REPORT
These are set-only commands. EXECute executes a DPOJET report save
operation for the currently defined report configuration. APPEnd appends new
data to the selected report.
486
Syntax
DPOJET:REPORT {EXECute | APPEnd}
Inputs
{EXECute | APPEnd}
DPOJET Printable Application Help
GPIB commands
DPOJET:REPORT:APPlicationconfig
This command turns on or off including complete application configuration in
reports.
Syntax
DPOJET:REPORT:APPlicationconfig {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:REPORT:AUTOincrement
This command turns on or off auto increment of report file names.
Syntax
DPOJET:REPORT:AUTOincrement {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
487
GPIB commands
DPOJET:REPORT:COMments
This command sets or queries the comments.
Syntax
DPOJET:REPORT:COMments <string>
DPOJET:REPORT:COMments?
Inputs
<string>
Outputs
<string>
DPOJET:REPORT:DETailedresults
This command turns on or off including detailed results in reports.
488
Syntax
DPOJET:REPORT:DETailedresults {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:REPORT:DISPunits
This command turns on or off displaying units in separate column
Syntax
DPOJET:REPORT:DISPunits {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:REPORT:ENABlecomments
This command sets or queries the comments enable or disable settings.
Syntax
DPOJET:REPORT:ENABlecomments {1 | 0}
DPOJET:REPORT:ENABlecomments?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
489
GPIB commands
DPOJET:REPORT:PASSFailresults
This command turns on or off including pass/fail results in reports.
Syntax
DPOJET:REPORT:PASSFailresults {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:REPORT:PLOTimages
This command turns on or off including detailed plot images in reports.
490
Syntax
DPOJET:REPORT:PLOTimages {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
GPIB commands
DPOJET:REPORT:REPORTName
This command sets the current report file name.
Syntax
DPOJET:REPORT:REPORTName <string>
Inputs
<string>
Outputs
<string>
DPOJET:REPORT:SETupconfig
This command turns on or off including setup configuration in reports.
Syntax
DPOJET:REPORT:SETupconfig {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
491
GPIB commands
DPOJET:REPORT:SAVEWaveforms
This command turns on or off saving waveforms when a report save/append is
invoked.
Syntax
DPOJET:REPORT:SAVEWaveforms {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:REPORT:STATE?
This query-only command provides the report status.
Syntax
Outputs
492
DPOJET:REPORT:STATE?
INPROGRESS | DONE
DPOJET Printable Application Help
GPIB commands
DPOJET:REPORT:VIEWreport
This command turns on or off viewing report after generation.
Syntax
DPOJET:REPORT:VIEWreport {1 | 0}
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET:RESULts:STATus?
This query-only command returns the overall pass/fail status.
Syntax
Outputs
DPOJET:RESULts:STATus?
{PASS | FAIL}
DPOJET:RESULts:VIew
This command sets or queries the results view type.
Syntax
DPOJET:RESULts:VIew {SUMmary | DETails}
DPOJET:RESULts:VIew?
DPOJET Printable Application Help
493
GPIB commands
Inputs
{SUMmary | DETails}
Outputs
{SUMmary | DETails}
DPOJET:SAVE
This set-only command saves the specified DPOJET measurement result to the
specified ref. For Example: DPOJET:SAVE MEAS4, REF2.
Syntax
DPOJET:SAVE {MEAS1-MEAS99 | REF1-REF4}
Inputs
{MEAS1-MEAS99 | REF1-REF4}
DPOJET:SOURCEAutoset
This command performs a DPOJET horizontal, vertical, or autoset on both
horizontal and vertical for any sources used in current measurements.
494
Syntax
DPOJET:SOURCEAutoset {HORIzontal | VERTical | BOTH}
Inputs
{HORIzontal | VERTical | BOTH}
DPOJET Printable Application Help
GPIB commands
DPOJET:SOURCEAutoset:HORizontal:UICount
This command sets or queries the UICount for horizontal autoset.
Syntax
DPOJET:SOURCEAutoset:HORizontal:UICount <NR3>
DPOJET:SOURCEAutoset:HORizontal:UICount?
Inputs
Outputs
<NR3>. Default is 10000.
<NR3>
DPOJET:SOURCEAutoset:HORizontal:UIValue
This command sets or queries the UI value for horizontal autoset.
Syntax
DPOJET:SOURCEAutoset:HORizontal:UIValue <NR3>
DPOJET:SOURCEAutoset:HORizontal:UIValue?
Inputs
<NR3>
Outputs
<NR3>
DPOJET Printable Application Help
495
GPIB commands
DPOJET:SOURCEAutoset:STATE?
This query-only command provides the Source Autoset status.
Syntax
Outputs
DPOJET:SOURCEAutoset:STATE?
RUNNING | STOPPED
DPOJET:STATE
This command sets or queries the current measurement state of DPOJET.
Syntax
DPOJET:STATE {RUN | SINGLE | RECALC | CLEAR | STOP}
DPOJET:STATE?
Inputs
Outputs
496
{RUN | SINGLE | RECALC | CLEAR | STOP}
The current state of the DPOJET measurement sequencer, including any of the
possible inputs.
DPOJET Printable Application Help
GPIB commands
DPOJET:UNITType
This command sets or queries the current unit-type setting for DPOJET, either
Unit Interval, or seconds.
Syntax
DPOJET:UNITType {UNITinterval | SEConds}
DPOJET:UNITType?
Inputs
{UNITinterval | SEConds}
Outputs
{UNITinterval | SEConds}
DPOJET:LOCKRJ
This command sets or queries the Lock RJ Value.
Syntax
DPOJET:LOCKRJ {1 | 0 }
DPOJET:LOCKRJ?
Inputs
{1 | 0}
Outputs
{1 | 0}
DPOJET Printable Application Help
497
GPIB commands
DPOJET:LOCKRJValue
This command sets or queries the LockRJValue.
Syntax
DPOJET:LOCKRJValue <NR3>
DPOJET:LOCKRJValue?
Inputs
{ Min = 1fs, Max = 1s}
Outputs
DPOJET:PLOT(x):BATHtub:XAXISUnits
This command sets or queries the X-Axis Units of Bathtub.
Syntax
DPOJET:PLOT<x>:BATHtub:XAXISUnits { UNITIntervals | SECOnds }
DPOJET:PLOT<x>:BATHtub:XAXISUnits?
498
Inputs
{ UNITIntervals | SECOnds }
Outputs
{ UNITIntervals | SECOnds }
DPOJET Printable Application Help
GPIB commands
DPOJET:PLOT(x):NOISEBATHtub:YAXISUnits
This command sets or queries the Y-Axis Units of Noise Bathtub.
Syntax
DPOJET:PLOT<x>:NOISEBATHtub:YAXISUnits { UNITAmplitudes |
VOLTs }
DPOJET:PLOT<x>:NOISEBATHtub:YAXISUnits?
Inputs
{ UNITAmplitudes | VOLTs }
Outputs
{ UNITAmplitudes | VOLTs }
DPOJET:VERTUNITType
This command sets or queries the vertical Unit.
Syntax
DPOJET:VERTUNITType {UNITamplitude | VOLts}
DPOJET:VERTUNITType?
Inputs
{UNITamplitude | VOLts}
Outputs
{UNITamplitude | VOLts}
DPOJET:VERsion?
This query-only command returns the current DPOJET version string.
Syntax
Outputs
DPOJET:VERsion?
<string>
DPOJET Printable Application Help
499
GPIB commands
500
DPOJET Printable Application Help
Index
- Duty Cycle, 26
-CC-Duty, 26
(SSC), 100
+ CC-Duty, 26
+Duty Cycle, 26
A
About DPOJET
Help > About DPOJET, 9
About PLL loop BW, 59
AC common mode, 288
AC Common Mode, 32
Advanced explicit Clock-Edge, 65
Advanced explicit clock-PLL, 67
Advanced filter configure parameters, 224
Algorithms, 259
Analysis method, 136
Application Directories
installation directory for DPOJET, 13
Apply to all, 61
Argument Types, 336
Auto calc every acq, 53, 54
Auto calc first acq, 53, 54
Autocalc every acq, 53
Autocalc first acq, 53
Autoset, 126
Autoset Parameters, 213
Autoset ref levels, 130
B
Band Pass, 46
Bathtub, 169
Bathtub plot parameters, 227
BER eye contour plot parameters, 228
BER eye plot parameters, 229
Bit config
eue high, 69
eye low, 69
Q-factor, 69
Bit config for amplitude, 76
Bit config for eye height, 69
DPOJET Printable Application Help
Bit config for Height@BER - Jitter + Nose, 71
Bit config for Height@BER - Jitter only, 70
Bit config for mask hits, 73
Bit config for TN@BER, 72
Bit config parameters, 217
blanking duration, 50
Blanking time, 51
Breakdown of jitter, 234
Breakdown of noise, 236
Brick wall, 48
Brick wall filter, 48
Browse, 11
C
CC-Period, 26, 263
Check Boxes, 11
Clear, 19
Clear log, 133
Clock edge, 64, 65
Clock Edge, 68
Clock multiplier, 64, 65
Clock Multiplier, 68
Clock recovery, 51
Clock recovery advanced setup, 56
clock recovery methods, 51
Clock recovery parameters, 221
Clock source, 64
CM V, 32
Comma separated value, 143
Command button, 11
compatibility, 8
Compatibility, 8
Composite Jitter Hist, 169
Composite jitter histogram plot parameters, 228
Composite noise histogram plot parameters, 228
Configure, 20, 176
Configure a BER Eye contour plot, 188
Configure a BER Eye plot, 189
Configure a Correlated Eye plot, 189
Configure a PDF Eye plot, 190
Configure autosets, 109
501
Index
Configure measurement-Jitter summary, 106
Configure measurement-Skew, 105
Configuring a noise bathtub plot, 187
Configuring bathtub plot, 175
Configuring bus states, 84
Configuring edges for CC-Period, 91
Configuring edges for DCD, 92
Configuring edges for DDR tCH, 98
Configuring edges for DDR tCL, 98
Configuring edges for DDR tERR(m-n), 98
Configuring edges for DDR tERR(n), 99
Configuring edges for DDR tHZDQ, 99
Configuring edges for DDR tLZDQ, 99
Configuring edges for DDRJIT, 100
Configuring edges for DDRtCK, 100
Configuring edges for differential crossOver, 89
Configuring edges for duty cycle, 91
Configuring edges for F/N - Jitter + Noise, 97
Configuring edges for F/N - Jitter Only, 96
Configuring edges for fall slew rate, 93
Configuring edges for hold, 91
Configuring edges for N-Period, 90
Configuring edges for overshoot, 92
Configuring edges for phase noise, 89
Configuring edges for rise slew rate, 93
Configuring edges for setup, 91
Configuring edges for skew, 88
Configuring edges for time outside level, 95
Configuring edges for undershoot, 92
Configuring histogram plot, 178
Configuring phase noise plot, 180
Configuring plots, 174
Configuring spectrum plot, 176
Configuring time trend, 177
Configuring transfer plot, 179
Connecting to a device under test (DUT), 22
Constant clock - fixed, 52, 55
Constant clock - mean, 52
Constant clock - median, 52, 54
Control panel, 19
Control Panel Parameters, 217
Conventions, 2
Correlated eye plot parameters, 229
502
Cursors and reset cursors, 191
Cursors in a plot, 193
Custom Measurement Name, 39
Custom source name, 112
Customer Feedback, 3
Cycle Max, 33
Cycle Min, 33
Cycle Pk-Pk, 33
D
Damping, 60
Data Array, 168
Data Logging Parameters, 216
Data logging-Measurement, 145
Data logging-Statistics, 143
DC common mode, 288
DC Common Mode, 32
DCD, 27, 268
DDJ, 27, 268
DDR Hold-Diff, 33
DDR Hold-SE, 33
DDR Over Area, 34
DDR Setup-Diff, 33
DDR Setup-SE, 33
DDR tCH(avg), 33
DDR tCK(avg), 33
DDR tCL(avg), 33
DDR tDQSQ-Diff, 302
DDR tDQSS, 34
DDR tERR(m-n), 33
DDR tERR(n), 33
DDR tJIT(duty), 34
DDR tJIT(per), 34
DDR tPST, 34
DDR tRPRE, 34
DDR tWPRE, 34
DDR Under Area, 34
DDR VID(ac), 34
DDR105, 241
DDR106, 242
DDR107, 242
DDR2tDQSCK, 300
DDR3 Vix(ac), 34
DPOJET Printable Application Help
Index
DDRtJIt(per), 100
Description, 161
Deskew, 22
Deskew Parameters, 215
Details, 164
DJ, 27, 266
DPOJET, xix, 2
Dual Dirac Deterministic Jitter, 266
Dual Dirac model, 136
Dual Dirac Random Jitter, 265
DUT, 2
Duty Cy-Cy, 26
E
E1001, 238
E1002, 238
E1003, 238
E1004, 238
E1005, 238
E1006, 238
E1007, 238
E1008, 238
E1009, 238
E1010, 238
E1012, 239
E1013, 239
E102, 238
E1020, 239
E1021, 239
E1022, 239
E1026, 239
E1027, 239
E1028, 239
E1029, 239
E103, 238
E1035, 239
E104, 238
E1040, 239
E105, 238
E1054, 239
E1055, 239
E1056, 239
E1057, 239
DPOJET Printable Application Help
E1058, 239
E1059, 239
E106, 238
E1060, 239
E1061, 239
E1062, 239
E1063, 239
E109, 238
E2001, 239
E2002, 239
E2003, 239
E2004, 239
E2005, 239
E2006, 239
E2007, 240
E2008, 240
E202, 238
E3001, 240
E3002, 240
E3003, 240
E3004, 240
E3005, 240
E3006, 240
E3007, 240
E3008, 240
E3010, 240
E3011, 240
E3012, 240
E400, 238
E4000, 240
E4001, 240
E4002, 240
E4003, 240
E4004, 240
E4005, 240
E4006, 240
E4007, 240
E4013, 240
E4014, 240
E4015, 241
E4016, 241
E4017, 241
E4018, 241
503
Index
E4019, 241
E4020, 241
E4021, 241
E4022, 241
E4023, 241
E4024, 241
E4027, 241
E4028, 241
E4029, 241
E4030, 241
E4031, 241
E4032, 241
E4033, 241
E4034, 241
E4035, 241
E411, 238
E424, 238
E425, 238
E500, 238
Edge increment, 90
Edges configuration for Jitter + Noise measurements,
87
Edges configuration for Jitter Only measurements, 86
Error log file, 13
Explicit clock recovery, 63
Explicit clock-edge, 64
Explicit clock-PLL, 66
Export data snapshot-Measurement, 140
Export data snapshot-Statistics, 139
Export figure, 191
Export measurement summary, 142
Export results to Ref, 165
Exporting plot files, 194
Eye analysis, 5
Eye Diagram, 169
Eye diagram for mask hits, 183
Eye diagram plot for eye height, 181
Eye diagram plot parameters, 226
Eye height, 283
Eye high, 284
Eye low, 285
Eye summary, 110
Eye width, 282
504
F
Fall slew rate, 95, 278
Fall time, 275
Fall Time, 30
Filter Spec, 47
Filters, 46
Filters parameters, 224
Five-Time Free Trial, 1
Freq (F1), 47
Freq (F2), 47
Frequency, 26, 261
G
Gating, 41
General, 39
General parameters, 225
Global, 40
Global parameters, 225
GPIB Commands
DPOJET:PLOT:BATHtub:XAXISUnits, 498
DPOJET:PLOT:COMPOSITENoisehist:TN, 471
DPOJET:ADDMeas, 336
DPOJET:ADDPlot, 423
DPOJET:ANALYSISMETHOD, 352
DPOJET:BURSTConfig:BUS, 337
DPOJET:BURSTConfig:CSACTIve, 338
DPOJET:BURSTConfig:CSSource, 338
DPOJET:BURSTConfig:CUSTOMRate, 339
DPOJET:BURSTConfig:DATA, 339
DPOJET:BURSTConfig:DATARate, 340
DPOJET:BURSTConfig:DETECTMethod, 340
DPOJET:BURSTConfig:GENERation, 341
DPOJET:BURSTConfig:LATEncy, 341
DPOJET:BURSTConfig:LENGth, 342
DPOJET:BURSTConfig:SEARch, 342
DPOJET:BURSTConfig:STRObe, 343
DPOJET:BURSTConfig:TOLERance, 343
DPOJET:CLEARALLMeas, 344
DPOJET:CLEARALLPlots, 424
DPOJET:DESKEW, 344
DPOJET:DESKEW:DESKEWchannel, 344
DPOJET Printable Application Help
Index
DPOJET:DESKEW:DESKEWHysteresis, 345
DPOJET:DESKEW:DESKEWMidlevel, 345
DPOJET:DESKEW:EDGE, 346
DPOJET:DESKEW:MAXimum, 346
DPOJET:DESKEW:MINimum, 347
DPOJET:DESKEW:REFChannel, 347
DPOJET:DESKEW:REFHysteresis, 348
DPOJET:DESKEW:REFMidlevel, 348
DPOJET:DIRacmodel, 349
DPOJET:EXPORT, 349
DPOJET:GATING, 350
DPOJET:HALTFreerunonlimfail, 350
DPOJET:HIGHPerfrendering, 351
DPOJET:INTERp, 351
DPOJET:LASTError?, 353
DPOJET:LIMITRise, 353
DPOJET:LIMits:FILEName, 354
DPOJET:LIMits:STATE, 355
DPOJET:LOCKRJ, 497
DPOJET:LOCKRJValue, 498
DPOJET:LOGging:MEASurements:FOLDer, 355
DPOJET:LOGging:MEASurements:STATE, 356
DPOJET:LOGging:SNAPshot, 356
DPOJET:LOGging:STATistics:FILEname, 357
DPOJET:LOGging:STATistics:STATE, 357
DPOJET:LOGging:WORSTcase:FOLDer, 358
DPOJET:LOGging:WORSTcase:STATE, 358
DPOJET:MEAS, 359
DPOJET:MEAS:BER:TARGETBER, 359
DPOJET:MEAS:BITCfgmethod, 360
DPOJET:MEAS:BITConfig:ENDPercent, 361
DPOJET:MEAS:BITConfig:NUMBins, 362
DPOJET:MEAS:BITConfig:STARTPercent, 361
DPOJET:MEAS:BITPcnt, 360
DPOJET:MEAS:BITType, 362
DPOJET:MEAS:BUSState:CLOCKPolarity, 363
DPOJET:MEAS:BUSState:FROMPattern, 363
DPOJET:MEAS:BUSState:FROMSymbol, 364
DPOJET:MEAS:BUSState:MEASBUSType, 364
DPOJET:MEAS:BUSState:MEASUREFROM,
365
DPOJET:MEAS:BUSState:MEASURETO, 365
DPOJET:MEAS:BUSState:TOPattern, 366
DPOJET Printable Application Help
DPOJET:MEAS:BUSState:TOSymbol, 366
DPOJET:MEAS:CLOCKRecovery:BWType, 370
DPOJET:MEAS:CLOCKRecovery:
CLOCKBitrate, 367
DPOJET:MEAS:CLOCKRecovery:
CLOCKFrequency, 367
DPOJET:MEAS:CLOCKRecovery:
CLOCKMultiplier, 368
DPOJET:MEAS:CLOCKRecovery:CLOCKPath,
368
DPOJET:MEAS:CLOCKRecovery:DAMPing,
369
DPOJET:MEAS:CLOCKRecovery:DATARate,
369
DPOJET:MEAS:CLOCKRecovery:
LOOPBandwidth, 370
DPOJET:MEAS:CLOCKRecovery:
MEANAUTOCalculate, 371
DPOJET:MEAS:CLOCKRecovery:METHod, 371
DPOJET:MEAS:CLOCKRecovery:MODel, 372
DPOJET:MEAS:CLOCKRecovery:
NOMINALOFFset, 372
DPOJET:MEAS:CLOCKRecovery:
NOMINALOFFset:Auto?, 373
DPOJET:MEAS:CLOCKRecovery:
NOMINALOFFset:Manual, 373
DPOJET:MEAS:CLOCKRecovery:
NOMINALOFFset:Recalctype, 374
DPOJET:MEAS:CLOCKRecovery:
NOMINALOFFset:Selectiontype, 374
DPOJET:MEAS:CLOCKRecovery:PATTern, 375
DPOJET:MEAS:CLOCKRecovery:STAndard,
375
DPOJET:MEAS:COMMONMode:FILTers:
STATE, 376
DPOJET:MEAS:CUSTomname, 376
DPOJET:MEAS:DATA?, 377
DPOJET:MEAS:DDR:MPERCycle, 377
DPOJET:MEAS:DDR:NPERCycle, 378
DPOJET:MEAS:DDR:WINDowsize, 378
DPOJET:MEAS:DPOJET:MEAS:REFVoltage,
385
DPOJET:MEAS:EDGE1, 379
DPOJET:MEAS:EDGE2, 379
DPOJET:MEAS:EDGEIncre, 380
505
Index
DPOJET:MEAS:EDGES:FROMLevel, 380
DPOJET:MEAS:EDGES:LEVel, 381
DPOJET:MEAS:EDGES:SLEWRATETechnique,
381
DPOJET:MEAS:EDGES:TOLevel, 382
DPOJET:MEAS:FILTers:BLANKingtime, 382
DPOJET:MEAS:FILTers:HIGHPass:FREQ, 383
DPOJET:MEAS:FILTers:HIGHPass:SPEC, 383
DPOJET:MEAS:FILTers:LOWPass:FREQ, 384
DPOJET:MEAS:FILTers:LOWPass:SPEC, 384
DPOJET:MEAS:FILTers:RAMPtime, 385
DPOJET:MEAS:FROMedge, 386
DPOJET:MEAS:HIGHREFVoltage, 386
DPOJET:MEAS:LOGging:MEASurements:
FILEname?, 387
DPOJET:MEAS:LOGging:MEASurements:
SELect, 388
DPOJET:MEAS:LOGging:WORSTcase:SELect,
389
DPOJET:MEAS:LOWREFVoltage, 387
DPOJET:MEAS:MASKfile, 389
DPOJET:MEAS:MASKOffset:HORIzontal:
AUTOfit?, 390
DPOJET:MEAS:MASKOffset:HORIzontal:
MANual, 391
DPOJET:MEAS:MASKOffset:HORIzontal:
SELECTIONtype, 390
DPOJET:MEAS:MEASRange, 392
DPOJET:MEAS:MEASRange:MAX, 391
DPOJET:MEAS:MEASRange:MIN, 392
DPOJET:MEAS:MEASStart, 393
DPOJET:MEAS:N, 393
DPOJET:MEAS:NAME?, 394
DPOJET:MEAS:PHASENoise:HIGHLimit, 388,
394
DPOJET:MEAS:PHASENoise:LOWLimit, 395
DPOJET:MEAS:REFVoltage, 395
DPOJET:MEAS:RESULts:ALLAcqs:
HITPopulation?, 396
DPOJET:MEAS:RESULts:ALLAcqs:HITS?, 397
DPOJET:MEAS:RESULts:ALLAcqs:LIMits:
HIgh:STATus?, 397
DPOJET:MEAS:RESULts:ALLAcqs:LIMits:
LOw:STATus?, 398
506
DPOJET:MEAS:RESULts:ALLAcqs:LIMits:
STATus?, 397
DPOJET:MEAS:RESULts:ALLAcqs:MAX:
STATus?, 399
DPOJET:MEAS:RESULts:ALLAcqs:MAX?, 398
DPOJET:MEAS:RESULts:ALLAcqs:MAXCC:
STATus?, 399
DPOJET:MEAS:RESULts:ALLAcqs:MAXCC?,
398
DPOJET:MEAS:RESULts:ALLAcqs:MAXHits?,
399
DPOJET:MEAS:RESULts:ALLAcqs:MEAN:
STATus?, 400
DPOJET:MEAS:RESULts:ALLAcqs:MEAN?,
400
DPOJET:MEAS:RESULts:ALLAcqs:MIN:
STATus?, 402
DPOJET:MEAS:RESULts:ALLAcqs:MIN?, 401
DPOJET:MEAS:RESULts:ALLAcqs:MINCC:
STATus?, 401
DPOJET:MEAS:RESULts:ALLAcqs:MINCC?,
401
DPOJET:MEAS:RESULts:ALLAcqs:MINHits?,
402
DPOJET:MEAS:RESULts:ALLAcqs:PK2PK?,
402, 403
DPOJET:MEAS:RESULts:ALLAcqs:
POPUlation:STATus?, 404
DPOJET:MEAS:RESULts:ALLAcqs:
POPUlation?, 403
DPOJET:MEAS:RESULts:ALLAcqs:SEG:Hits?,
404
DPOJET:MEAS:RESULts:ALLAcqs:SEG:
MAXHits?, 404
DPOJET:MEAS:RESULts:ALLAcqs:SEG:
MINHits?, 405
DPOJET:MEAS:RESULts:ALLAcqs:STDDEV:
STATus?, 406
DPOJET:MEAS:RESULts:ALLAcqs:STDDev?,
405
DPOJET:MEAS:RESULts:ALLAcqs?, 396
DPOJET:MEAS:RESULts:CURRentacq:MAX:
STATus?, 407
DPOJET:MEAS:RESULts:CURRentacq:MAX?,
406
DPOJET Printable Application Help
Index
DPOJET:MEAS:RESULts:CURRentacq:
MAXCC:STATus?, 407
DPOJET:MEAS:RESULts:CURRentacq:
MAXCC?, 406
DPOJET:MEAS:RESULts:CURRentacq:MEAN:
STATus?, 408
DPOJET:MEAS:RESULts:CURRentacq:MEAN?,
408
DPOJET:MEAS:RESULts:CURRentacq:MIN:
STATus?, 409
DPOJET:MEAS:RESULts:CURRentacq:MIN?,
408
DPOJET:MEAS:RESULts:CURRentacq:MINCC:
STATus?, 409
DPOJET:MEAS:RESULts:CURRentacq:
MINCC?, 409
DPOJET:MEAS:RESULts:CURRentacq:PK2PK:
STATus?, 410
DPOJET:MEAS:RESULts:CURRentacq:
PK2PK?, 410
DPOJET:MEAS:RESULts:CURRentacq:
POPUlation:STATus?, 411
DPOJET:MEAS:RESULts:CURRentacq:
POPUlation?, 411
DPOJET:MEAS:RESULts:CURRentacq:
STDDev:STATus?, 412
DPOJET:MEAS:RESULts:CURRentacq:
STDDev?, 411
DPOJET:MEAS:RESULTS:STATus?, 412
DPOJET:MEAS:RESULts:VIew?, 413
DPOJET:MEAS:RESULts?, 396
DPOJET:MEAS:RJDJ:BER, 413
DPOJET:MEAS:RJDJ:DETECTPLEN, 414
DPOJET:MEAS:RJDJ:PATLen, 414
DPOJET:MEAS:RJDJ:TYPe, 415
DPOJET:MEAS:RJDJ:WINDOwlength, 415
DPOJET:MEAS:RNDN:AUTODETECTpattern,
416
DPOJET:MEAS:RNDN:BER, 416
DPOJET:MEAS:RNDN:PATLen, 417
DPOJET:MEAS:RNDN:TYPe, 417
DPOJET:MEAS:RNDN:WINDOwlength, 418
DPOJET:MEAS:SIGNALType, 418
DPOJET:MEAS:SOUrce1, 419
DPOJET:MEAS:SOUrce2, 419
DPOJET Printable Application Help
DPOJET:MEAS:SSC::NOMinalfreq:
SELECTIONtype, 421
DPOJET:MEAS:SSC:NOMinalfreq:AUTO?, 420
DPOJET:MEAS:SSC:NOMinalfreq:MANual, 420
DPOJET:MEAS:TIMEDATa?, 421
DPOJET:MEAS:TOEdge, 422
DPOJET:MEAS:ZOOMEVENT, 422
DPOJET:MINBUJUI, 354
DPOJET:NUMMeas?, 423
DPOJET:PLOT:BATHtub:BER, 442
DPOJET:PLOT:BATHtub:VERTical:SCALE,
443
DPOJET:PLOT:BERContour:ALIGNment, 454
DPOJET:PLOT:BERContour:BER1E12, 458
DPOJET:PLOT:BERContour:BER1E15, 458
DPOJET:PLOT:BERContour:BER1E18, 459
DPOJET:PLOT:BERContour:BER1E6, 457
DPOJET:PLOT:BERContour:BER1E9, 457
DPOJET:PLOT:BERContour:HORizontal:
AUTOscale, 455
DPOJET:PLOT:BERContour:HORizontal:
RESolution, 455
DPOJET:PLOT:BERContour:MASK, 455
DPOJET:PLOT:BERContour:MASKFile, 456
DPOJET:PLOT:BERContour:SUPERImpose, 456
DPOJET:PLOT:BERContour:TARGETBER, 459
DPOJET:PLOT:BEREye:BER1E12V, 468
DPOJET:PLOT:BEREye:BER1E15V, 468
DPOJET:PLOT:BEREye:BER1E18V, 469
DPOJET:PLOT:BEREye:BER1E6V, 467
DPOJET:PLOT:BEREye:BER1E9V, 467
DPOJET:PLOT:BEREye:TARGETBER, 469
DPOJET:PLOT:COMPOSITEJitterhist:DDJDCD,
427
DPOJET:PLOT:COMPOSITEJitterhist:
NUMBins, 425
DPOJET:PLOT:COMPOSITEJitterhist:PJ, 426
DPOJET:PLOT:COMPOSITEJitterhist:RJNPJ,
426
DPOJET:PLOT:COMPOSITEJitterhist:TJ, 425
DPOJET:PLOT:COMPOSITEJitterhist:
VERTical:SCALE, 424
DPOJET:PLOT:COMPOSITENoisehist:
DDNONE, 473
507
Index
DPOJET:PLOT:COMPOSITENoisehist:
DDNZERO, 472
DPOJET:PLOT:COMPOSITENoisehist:
HORIzontal:SCALE, 470
DPOJET:PLOT:COMPOSITENoisehist:
NUMBins, 470
DPOJET:PLOT:COMPOSITENoisehist:PN, 472
DPOJET:PLOT:COMPOSITENoisehist:RNNPN,
471
DPOJET:PLOT:CORRELATEDEye:BER1E12V,
462
DPOJET:PLOT:CORRELATEDEye:BER1E15V,
462
DPOJET:PLOT:CORRELATEDEye:BER1E18V,
463
DPOJET:PLOT:CORRELATEDEye:BER1E6V,
461
DPOJET:PLOT:CORRELATEDEye:BER1E9V,
461
DPOJET:PLOT:CORRELATEDEye:
TARGETBER, 463
DPOJET:PLOT:DATA:XDATa:DDNONE?, 433
DPOJET:PLOT:DATA:XDATa:DDNZERO?,
432
DPOJET:PLOT:DATA:XDATa:PJ?, 429
DPOJET:PLOT:DATA:XDATa:PN?, 432
DPOJET:PLOT:DATA:XDATa:RNNPN?, 431
DPOJET:PLOT:DATA:XDATa:TJ?, 428
DPOJET:PLOT:DATA:XDATa:TN?, 431
DPOJET:PLOT:DATA:XDATa?, 427
DPOJET:PLOT:DATA:YDATa:DDJDCD?, 436
DPOJET:PLOT:DATA:YDATa:DDNONE?, 439
DPOJET:PLOT:DATA:YDATa:DDNZERO?,
439
DPOJET:PLOT:DATA:YDATa:PJ?, 435
DPOJET:PLOT:DATA:YDATa:PN?, 438
DPOJET:PLOT:DATA:YDATa:RNNPN?, 437
DPOJET:PLOT:DATA:YDATa:TJ?, 434
DPOJET:PLOT:DATA:YDATa:TN?, 437
DPOJET:PLOT:DATA:YDATa?, 433
DPOJET:PLOT:EYE:ALIGNment, 443
DPOJET:PLOT:EYE:HORizontal:AUTOscale,
444
DPOJET:PLOT:EYE:HORizontal:RESolution,
444
508
DPOJET:PLOT:EYE:MASKfile, 445
DPOJET:PLOT:EYE:STATE, 445
DPOJET:PLOT:EYE:SUPERImpose, 446
DPOJET:PLOT:HISTOgram:AUTOset, 446
DPOJET:PLOT:HISTOgram:HORizontal:
AUTOscale, 447
DPOJET:PLOT:HISTOgram:HORizontal:
CENter, 447
DPOJET:PLOT:HISTOgram:HORizontal:SPAN,
448
DPOJET:PLOT:HISTOgram:NUMBins, 448
DPOJET:PLOT:HISTOgram:VERTical:SCALE,
449
DPOJET:PLOT:NOISEBATHtub:YAXISUnits,
499
DPOJET:PLOT:PDFEye:BER1E12V, 465
DPOJET:PLOT:PDFEye:BER1E15V, 465
DPOJET:PLOT:PDFEye:BER1E18V, 466
DPOJET:PLOT:PDFEye:BER1E6V, 464
DPOJET:PLOT:PDFEye:BER1E9V, 464
DPOJET:PLOT:PDFEye:TARGETBER, 466
DPOJET:PLOT:PHASEnoise:BASEline, 449
DPOJET:PLOT:SOUrce?, 441
DPOJET:PLOT:SPECtrum:BASE, 450
DPOJET:PLOT:SPECtrum:HORizontal:SCALE,
450
DPOJET:PLOT:SPECtrum:MODE, 451
DPOJET:PLOT:SPECtrum:VERTical:SCALE,
451
DPOJET:PLOT:TRANSfer:DENominator, 452
DPOJET:PLOT:TRANSfer:HORizontal:SCALE,
452
DPOJET:PLOT:TRANSfer:MODE, 453
DPOJET:PLOT:TRANSfer:NUMerator, 453
DPOJET:PLOT:TRANSfer:VERTical:SCALE,
454
DPOJET:PLOT:TREND:TYPe, 441
DPOJET:PLOT:TYPe?, 442
DPOJET:PLOT:VERTBATHtub:BER, 460
DPOJET:PLOT:VERTBATHtub:HORIzontal:
SCALE, 460
DPOJET:PLOT:XUnits?, 440
DPOJET:PLOT:YUnits?, 440
DPOJET:PLOTx:DATA:XDATa:RJBUJ?, 429
DPOJET Printable Application Help
Index
DPOJET:PLOTx:DATA:YDATa:RJBUJ?, 435
DPOJET:POPULATION:CONDition, 473
DPOJET:POPULATION:LIMIT, 474
DPOJET:POPULATION:LIMITBY, 474
DPOJET:POPULATION:STATE, 475
DPOJET:QUALify:ACTIVE, 475
DPOJET:QUALify:SOUrce, 476
DPOJET:QUALify:STATE, 476
DPOJET:REFLevel:CH:MIDZero, 477
DPOJET:REFLevels:AUTOSet, 477
DPOJET:REFLevels:CH:ABsolute, 479
DPOJET:REFLevels:CH:ABsolute:FALLHigh,
480
DPOJET:REFLevels:CH:ABsolute:FALLLow,
481
DPOJET:REFLevels:CH:ABsolute:FALLMid,
481
DPOJET:REFLevels:CH:ABsolute:HYSTeresis,
482
DPOJET:REFLevels:CH:ABsolute:RISEHigh,
479
DPOJET:REFLevels:CH:ABsolute:RISELow,
479
DPOJET:REFLevels:CH:ABsolute:RISEMid, 480
DPOJET:REFLevels:CH:AUTOSet, 478
DPOJET:REFLevels:CH:BASETop, 482
DPOJET:REFLevels:CH:PERcent, 483
DPOJET:REFLevels:CH:PERcent:FALLHigh,
483
DPOJET:REFLevels:CH:PERcent:FALLLow,
483
DPOJET:REFLevels:CH:PERcent:FALLMid, 484
DPOJET:REFLevels:CH:PERcent:HYSTeresis,
484
DPOJET:REFLevels:CH:PERcent:RISEHigh, 485
DPOJET:REFLevels:CH:PERcent:RISELow, 485
DPOJET:REFLevels:CH:PERcent:RISEMid, 486
DPOJET:REPORT, 486
DPOJET:REPORT:APPlicationconfig, 487
DPOJET:REPORT:AUTOincrement, 487
DPOJET:REPORT:COMments, 488
DPOJET:REPORT:DETailedresults, 488
DPOJET:REPORT:ENABlecomments, 489
DPOJET:REPORT:PASSFailresults, 490
DPOJET Printable Application Help
DPOJET:REPORT:PLOTimages, 490
DPOJET:REPORT:REPORTName, 491
DPOJET:REPORT:SAVEWaveforms, 492
DPOJET:REPORT:SETupconfig, 491
DPOJET:REPORT:STATE?, 492
DPOJET:REPORT:VIEWreport, 493
DPOJET:RESULts:STATus?, 493
DPOJET:RESULts:VIew, 493
DPOJET:SAVE, 494
DPOJET:SOURCEAutoset, 494
DPOJET:SOURCEAutoset:HORizontal:UICount,
495
DPOJET:SOURCEAutoset:HORizontal:UIValue,
495
DPOJET:STATE, 496
DPOJET:UNITType, 497
DPOJET:VERsion?, 499
DPOJET:VERTUNITType, 499
GPIB Program, 335
GPIB Reference Materials, 335
H
Halt free-run, 214
Height, 31
Height@BER, 31, 284
High, 32, 287
High Pass filter, 46
High time, 276
High Time, 30
High-Low, 32, 290
Histogram, 168
Histogram plot parameters, 226
Hold, 30, 31, 279
Horizontal cursors, 193
Horizontal resolution, 118
Hysteresis, 159
I
Image export directory, 138
Installing the Application, 9
509
Index
J
Jitter analysis, 5
Jitter analysis through RJ-DJ separation, 326
Jitter estimation using Dual-Dirac, 328
Jitter measurements map, 234
Jitter separation model, 137
Jitter summary, 266
Jitter Summary, 27
JTF BW, 61
L
Limit, 45
Limits files, 13
Lock RJ Value, 136
Log notifiers, 15
Logging export directory, 138
Loop BW, 60
Low, 32, 287
Low Pass filter, 46
Low time, 276
Low Time, 30
Lower Frequency, 89
M
Mask files, 13
Mask hits, 286
Mask Hits, 32
Max, 161
Max or Min value, 39
Max-cc, 161
Mean, 161
Measurement Range, 39
Measurement Select Parameters, 211
Measurements-Amplitude, 32
Measurements-Eye, 31
Measurements-Period/Freq, 26
Measurements-Time, 30
Menu Shortcuts
Alt+A+J, 14
Min, 161
Min-cc, 162
Moving and resizing plots, 191
510
N
N-Period, 26
Navigation panel, 20
Neg Width, 26
Noise analysis, 5
Noise bathtub plot parameters, 228
Noise measurements map, 236
Nominal clock offset, 67
Notifier duration, 133
NPJ, 27
NPJ measurement, 268
O
One touch jitter, 101
Opposite as From, 88
Oscilloscope model number, 4
Overshoot, 32, 291
P
p-p, 161
Path defaults, 138
Pattern file name, 57
Pattern Type, 85
PCIe, 48
PCIe AC common mode, 315
PCIe AC Common Mode, 35
PCIe MAX-MIN Ratio, 35
PCIe Med-Mx-Jitter, 35, 255
PCIe SSC FREQ DEV, 35
PCIe SSC PROFILE, 35
PCIe T-RF-Mismch, 35, 255
PCIe T-TX, 34, 256
PCIe T-Tx-Diff-PP, 34, 256
PCIe T-Tx-Fall, 34, 256
PCIe T-Tx-Rise, 35, 256
PCIe T/nT Ratio, 34, 256
PCIe Tmin-Pulse, 34, 256
PCIe UI, 35, 256
PDF eye plot parameters, 229
Period, 26
DPOJET Printable Application Help
Index
Phase noise, 267
Phase Noise, 27, 169
Phase noise plot parameters, 227
PJ, 27, 267
PLL clock recovery setup, 58
PLL Custom BW, 62
PLL model, 60
PLL standard BW, 60
Plot files, 13
Plot summary views, 191
Plot usage, 170
Plots, 20
Population, 45, 85, 161
Pos Width, 26
Positive and negative CC duty, 263
Positive and negative duty cycle, 262
Positive and negative width, 260
Preferences Parameters, 214
Preferences-General, 133
Preferences-Jitter Decomp, 136
Preferences-Measurement, 134
Print figure, 191
Printing plots, 194
Probes, 8
Product description, 5
Progress indicator, 153
Q
Q-Bathtub, 169
Q-factor, 285
Q-PulseWidth, 169
Qualify
Horizontal Sample Rate, 42
R
Ramp time, 51
Recalc, 19
recall, 16
Recalling a Default Setup, 17
Recalling a Saved Setup, 16
Ref level menu parameters, 213
Ref Levels Setup, 129
DPOJET Printable Application Help
reference levels, 124
Related Documentation, 2
Report export directory, 138
Report files, 13
Reports, 20, 194, 229
Reports format, 196
Requirements and Restrictions, 8
Results, 20, 332
Results as plots, 168
Returning to the Application, 15
Rise slew rate, 277
Rise time, 274
Rise Time, 30
Rising versus falling thresholds, 125
Rj, 265
RJ, 27
RJ-DJ
Auto, 78
Manual, 78
RJ-DJ analysis of arbitrary pattern, 80
RJ-DJ analysis of repeating pattern, 79
RJ-DJ analysis parameters, 223
RJ-DJ separation for arbitrary patterns, 327
RJ-DJ separation via spectrum analysis, 326
RN-DN
Auto, 81
Manual, 81
RN-DN analysis of arbitrary pattern, 83
RN-DN analysis of repeating pattern, 82
RN-DN analysis parameters, 223
Run, 19
S
Same as From, 88
Save Current Stats..., 162
Saving a Setup, 16
Select, 20
Select measurement, 104
Select sources, 107
Selecting a measurement, 24
Selecting plots, 173
Separation on non-periodic jitter, 327
Sequencing, 153
511
Index
Setup, 30, 276
Show plots, 20
Sine(x)/x, 135
Single, 19
Skew, 30, 275
Source autoset, 118
Spectrum, 168
Spectrum plot parameters, 226
Spread spectrum clocking
configuring, 111
Spread spectrum clocking (SSC), 100
SSC, 46
SSC FREQ DEV, 281
SSC FREQ DEV MAX, 280
SSC FREQ DEV MIN, 280
SSC mod rate, 280
SSC modulation, 111
SSC parameters, 223
SSCpProfile, 279
Standard
b/s, 61
Starting the Application, 11
Stat pop, 160
Statistical results, 161
Statistics log files, 13
Std Dev, 161
Steps to deskew probes and channels, 23
Summary, 164
Summary-Measurement, 158
Summary-Misc, 160
Summary-Ref levels, 159
Sync cursor, 191
T
T/nT ratio, 288
T/nT-Ratio, 32
Tab, 11
Table of measurements-jitter, 26
Table of measurements-Noise, 28
TCdr-Slew-Max, 36
tCMD-CMD, 281
Technical Support, 3
Test point, 36
512
Text editor, 15
TIE, 27, 264
Time outside level, 281
Time Trend, 168
Time trend plot parameters, 227
Timing analysis, 5
TJ, 27
TJ@BER, 266
Tmin-Pulse-Tj, 36
Toolbar functions in plot, 191
Transfer, 168
Transfer function plot parameters, 227
Tutorial, 201
two source, 116
U
Undershoot, 32, 291
Upper Frequency, 89
USB AC common mode, 325
USB AC Common Mode, 36
USB SSC MOD-RATE, 36
USB SSC PROFILE, 36
USB SSC-FREQ-DEV, 36
USB Tmin-Pulse-Dj, 36
USB UI, 36
user comments, 195
V
V-Diff-Xovr, 32, 290
Vertical cursors, 193
View log file, 140
Viewing plots, 190
virtual keypad, 12
VTx-Diff-PP, 36
W
W1011, 239
W1051, 239
W1053, 239
W1064, 239
W4008, 240
DPOJET Printable Application Help
Index
W4009, 240
W4025, 241
W4026, 241
W410, 238
Waveform, 169
Waveform files, 202
Waveform interpolation type, 135
Width, 31
DPOJET Printable Application Help
Width@BER, 31, 283
Window Length, 85
Worst case logging, 149
Z
Zoom and reset zoom, 191
Zoom in a plot, 192
513
Index
514
DPOJET Printable Application Help
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