Series it2000 User`s Manual

Series it2000 User`s Manual
RS-232 Transducer
Digital Communication
User’s Manual
Firmware Version 217928G
Stellar Technology Incorporated
Copyright Notice
© 2004 Stellar Technology Incorporated. All rights reserved.
This manual, as well as the software described in it, is furnished under license and may be used
or copied only in accordance with the terms of such license. The content of this manual is furnished for informational use only, is subject to change without notice, and should not be construed as a commitment by Stellar Technology Incorporated. Stellar Technology Incorporated
assumes no responsibility or liability for any errors or inaccuracies that may appear in this book.
Except as permitted by such license, no part of this publication may be reproduced, stored in a
retrieval system, or transmitted in any form or by any means, electronic, mechanical, recording,
or otherwise, without the prior written permission of Stellar Technology Incorporated.
it2000 is a trademarks of Stellar Technology Incorporated. it2000 logo and the STI logo are
trademarks of Stellar Technology Incorporated in the USA. Microsoft, Windows 9x/NT/2000/XP/
CE, Microsoft Access, and Microsoft Excel are registered trademarks of Microsoft Corporation. All
other products or name brands are the trademarks of their respective holders.
Part number: 222133 Rev A
Contents
Chapter 1: Installation.............................................................................................. 5
RS-232 Connector.......................................................................................................................................6
Communication Setup...............................................................................................................................7
Chapter 2: Quick-Start Tutorial................................................................................ 9
Basic Measurements ..................................................................................................................................10
Chapter 3: Using Commands ................................................................................... 11
Command and Query Structure ........................................................................................................12
Command Entry..................................................................................................................................13
Argument Types ..................................................................................................................................14
Command Usage Rules ......................................................................................................................16
Syntax Diagrams .................................................................................................................................16
Chapter 4: Command Reference.............................................................................. 17
Measure Subsystem ...................................................................................................................................18
MEAS:PRES..........................................................................................................................................18
MEAS:TEMP ........................................................................................................................................19
MEAS:ALL ............................................................................................................................................19
Test Commands..........................................................................................................................................20
TEST:INP .............................................................................................................................................20
TEST:OUTPV .......................................................................................................................................20
System Commands ....................................................................................................................................22
SYST:VERS:FIRM.................................................................................................................................22
*IDN .....................................................................................................................................................22
*RST......................................................................................................................................................22
OFFSET:SET ........................................................................................................................................23
SPAN:SET.............................................................................................................................................23
TURNDOWN:SET ...............................................................................................................................24
TIMER:SET ..........................................................................................................................................24
Index .......................................................................................................................... 27
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RS-232 Transducer Digital Communication User’s Manual
C
H A P T E R
1
Installation
This chapter describes the steps to install the RS-232 Transducer.
Contents
•
RS-232 Connector .........................................................................6
•
Communication Setup .................................................................7
6
RS-232 Transducer Digital Communication User’s Manual
RS-232 Connector
Serial data is transmitted and received using only three signals of the RS-232
connector. All digital output signals are galvanically isolated from the transducer
excitation supply.
5
4
9
3
8
2
7
1
6
Pin 2 - TxD
Pin 3 - RxD
Pin 5 - DGND
Figure 1-1: RS-232 pin assignments
Chapter 1: Installation
7
Communication Setup
The RS-232 Transducer uses an RS-232 interface as a means of communication
with a controller. The default communication parameters are as follows:
Setting
Baud rate
Data bits
Stop bits
Parity
Flow control
Table 1-1:
Value
9600
8
1
none
none
RS-232 communication settings
Commands are sent in ASCII text using the syntax described Chapter 3, “Using
Commands”. All commands must be terminated with a carriage-return / line-feed
combination or a line-feed-only character sequence.
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RS-232 Transducer Digital Communication User’s Manual
C
H A P T E R
2
Quick-Start Tutorial
This chapter gives you a quick guide on how to connect Series it2000 Pressure
Transducer and start using it’s basic functionality.
Contents
•
Basic Measurements .....................................................................10
10
RS-232 Transducer Digital Communication User’s Manual
Basic Measurements
To make basic digital pressure or temperature measurements you may use the
standard Windows Terminal program with appropriate settings.
Steps required to make one digital pressure measurement using the Terminal
program:
1. Run Terminal program
2. Set communication port settings
3. Type in the command: meas:pres? terminated with the command terminator
(see Chapter 3, “Using Commands”)
4. An example of a RS-232 Transducer response is shown below.
Figure 2-1: Windows Terminal program
For more commands see Chapter 4, “Command Reference”.
C
H A P T E R
3
Using Commands
The RS-232 Transducer is controlled through the RS-232 interface using a large
group of commands and queries. This chapter describes the syntax these
commands and queries use and the conventions the transducer uses to process
them. The commands and queries themselves are listed in Chapter 4, “Command
Reference”.
Contents
•
Command and Query Structure ...................................................16
•
Command Entry ............................................................................17
•
Argument Types ............................................................................18
•
Command Usage Rules .................................................................20
•
Syntax Diagrams ............................................................................20
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RS-232 Transducer Digital Communication User’s Manual
Commands are transmitted to the transducer using the American Standard Code
for Information Interchange (ASCII) character encoding.
This manual uses Backus-Naur Form (BNF) notation and syntax diagrams to
describe commands and queries. The following BNF symbols:
Symbol
< >
::=
|
{}
[]
...
()
Table 3-1:
Meaning
Defined element
Is defined as
Exclusive OR
Group; one element is required
Optional; can be omitted
Previous element(s) may be repeated
Comment
BNF Symbols and Meanings
Command and Query Structure
Commands consist of set commands and query commands (usually simply called
commands and queries). Commands modify instrument settings or tell the
transducer to perform a specific action. Queries cause the transducer to return
data and information about its status.
Most commands have both a set form and a query form. The query form of the
command is the same as the set form but with a question mark at the end. For
example, the set command INPut:GAIN has a query form INPut:GAIN?. Not all
commands have both a set and a query form; some commands are set only and
some are query only.
A command message is a command or query name, followed by any information
the transducer needs to execute the command or query. Command messages
consist of five different element types, defined as follows:
Symbol
Meaning
<Header>
The basic command name. If the header ends with a
question mark, the command is a query. The header
may begin with a colon (:) character; if the command is
concatenated with other commands the beginning
colon is required. The beginning colon can never be
used with a command beginning with an asterisk (*).
A header sub-function. Some commands headers have
only one mnemonic. If a command header has multiple
mnemonics, they are always separated from each other
by a colon (:) character.
<Mnemonic>
Chapter 3: Using Commands
13
Symbol
Meaning
<Argument>
<Comma>
<Space>
Table 3-2:
A quantity, quality, restriction, or limit associated with
the header. Not all commands have multiple
arguments. Arguments are separated from the header
by a <Space>. Arguments are separated from each
other by a <Comma>.
A single comma between arguments of multipleargument commands. It may optionally have white
space characters before and after the comma.
A white space character between command header
and argument. It may optionally consist of multiple
white space characters.
Command Message Elements
Header
Comma
WORKset:DEFAult SAMPLE,ON
Mnemonics
WORKset
:
DEFAult
Space
<Space>
Arguments
<name>
<comma>
<state>
Figure 3-1: Command Message Elements
Commands
Commands cause the transducer to perform a specific function or change one of
its settings. Commands have the structure:
<Header>[<Space><Argument>[<Comma><Argument>]...]
A command header is made up of one or more mnemonics arranged in a
hierarchical or tree structure. The first mnemonic is the base or root of the tree
and each subsequent mnemonic is a level or branch off the previous one.
Commands at a higher level in the tree may affect those at a lower level. The
leading colon (:) always returns you to the base of the command tree.
Queries
Queries cause the transducer to return information about its status or settings.
Queries have the structure:
<Header>?
<Header>?[<Space><Argument>[<Comma><Argument>]...]
Command Entry
Follow these general rules when entering commands:
• Commands can be entered in upper or lower case.
14
RS-232 Transducer Digital Communication User’s Manual
• Any command can be preceded with white space characters. White space
characters include any combination of the ASCII control characters 00
through 09 and 0B through 20 hexadecimal (0 through 9 and 11 through 32
decimal).
• The transducer ignores commands consisting of any combination of white
space characters and line feeds.
Suffixes
Some mnemonics have a plural form. The mnemonic that is expressed in plural
form indicates that it represents more than one instance of a subsystem. This is
illustrated as follows:
TEST:INP5?
All suffixes have a default value of one and is used when the suffix is not specified.
Suffixes are enclosed in brackets in the command syntax descriptions to indicate
their optional inclusion. The brackets are not to be included in actual usage.
Command Termination
All commands are terminated with a carriage-return / line-feed combination. The
SCPI specification also allows for the use of a line-feed character only. The ASCII
codes for these command terminators are as follows:
ASCII Code
10
13
Table 3-3:
Key Stroke
Control + j
Control + m
Description
Line feed
Carriage return
ASCII Codes for Command Termination
Argument Usage
All arguments listed for a command are mandatory and must be specified by at
least a placeholder. Multiple arguments must be separated by a comma. String
arguments are case-sensitive unless otherwise noted. Those arguments that are
actually mnemonics themselves follow the same abbreviation options as
described above.
Argument Types
The argument of a command may be in one of several forms. The individual
descriptions of each command tell which argument types to use with that
command.
Numeric Arguments
Many transducer commands require numerical arguments. The syntax shows the
format that the transducer returns in response to a query. This is also the
preferred format when sending the command to the transducer though it will
accept any of the formats. This manual represents these arguments as follows:
Chapter 3: Using Commands
15
Symbol
<NR1>
<NR2>
<NR3>
Table 3-4:
Meaning
Signed integer value
Floating point value without an exponent
Floating point value with an exponent
Numeric Argument Types
The transducer will automatically force most numeric arguments to a valid
setting, either by rounding or truncating, when you input an invalid number
unless otherwise noted in the command description.
Quoted String Arguments
Some commands accept or return data in the form of a quoted string, which is
simply a group of ASCII characters enclosed by a double quote (“). For example:
“this is a quoted string”
Symbol
<QString>
Table 3-5:
Meaning
Quoted string value
Quoted String Argument Type
Follow these rules when you use quoted strings:
• A quoted string can include any character defined in the 7-bit ASCII character
set.
• Strings can have upper or lower case characters.
• A string cannot be terminated with the END message before the closing
delimiter.
• The maximum length of a quoted string returned from a query is 256
characters.
Block Arguments
Some transducer commands use a block argument form:
Symbol
<NZDig>
<Dig>
<DChar>
<Block>
Table 3-6:
Meaning
a non-zero digit character, in the range 1-9
A digit character, in the range 0-9
A character with the hex equivalent of 00 through FF
hexadecimal (0 through 255 decimal)
A block of data bytes, defined as:
<Block> ::=
{ #<NZDig><Dig>[<Dig>...][<DChar>...]
| #0[<DChar>...]<terminator> }
Block Argument Types
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RS-232 Transducer Digital Communication User’s Manual
<NZDig> specifies the number of <Dig> elements that follow. Taken together, the
<Dig> elements form a decimal integer that specifies how many <DChar>
elements follow.
Command Usage Rules
It is important to keep the following rules in mind when using the commands in
this reference guide:
1. Commands are case-insensitive.
2. All commands are terminated by a carriage-return / line-feed combination or a
linefeed.
3. All arguments are required.
4. Multiple arguments must be separated by a comma.
5. String arguments are case-sensitive unless they are a mnemonic.
Syntax Diagrams
The syntax diagrams in this manual use the following symbols and notation:
• Circles and ovals contain literal elements. Most elements must be sent
exactly as shown. The diagrams show command mnemonics in both upper
and lower case to distinguish between complete and abbreviated spellings.
These elements are not case sensitive and you can omit the lower case
portion of the mnemonic.
• Boxes contain the defined elements described earlier in this section, such as
<NR3> or <QString>.
• Elements are connected by arrows that show the allowed paths through the
diagram, and thus the orders in which you can send the elements. Parallel
paths show that you must take one and only one of the paths. A path around a
group of elements shows that those elements are optional. Loops show
elements that can be repeated.
Here are some examples of typical syntax diagrams:
C
H A P T E R
4
Command Reference
This chapter describes each of the commands used to configure and control the
RS-232 Transducer. The command reference is broken down into several groups
of related functionality.
Contents
•
Measure Subsystem ......................................................................20
•
Test Commands ............................................................................22
•
System Commands .......................................................................24
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RS-232 Transducer Digital Communication User’s Manual
Measure Subsystem
The measure subsystem includes commands for initiating pressure and
temperature measurements.
MEAS:PRES
Returns a pressure measurement.
Syntax
MEAS:PRES?
MEAS
Remarks
:
PRES
?
The unit of measure is PSI.
Pressure output is fixed at 7 characters, with a first sign character followed by a
number with resolution based on a following table:
Example
Pressure range
Output format
0<=Range<5
5<=Range<50
50<=Range<500
500<=Range<5000
5000<=Range
±0.0000
±00.000
±000.00
±0000.0
±000000
meas:pres?
+14.135
Chapter 4: Command Reference
19
MEAS:TEMP
Returns a temperature measurement.
Syntax
MEAS:TEMP[channel]?
:
MEAS
Suffix
channel
Parameter
Result
none
Temperature from the on-chip temperature sensor
(default)
Temperature from the on-chip temperature sensor
Temperature from the RTD (optional)
0
1
Remarks
?
channel
TEMP
The unit of measure is degrees Fahrenheit.
Temperature output is fixed to the following format: ±000.00
Example
meas:temp?
+078.91
MEAS:ALL
Returns a pressure and temperature measurements.
Syntax
MEAS:ALL?
MEAS
:
ALL
?
Remarks
First value - pressure measurement, second value - on-chip temperature
measurement or RTD temperature if there is one present, third value (optional) on-chip temperature measurement if RTD is present.
Example
meas:all?
+078.50,+123.24
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RS-232 Transducer Digital Communication User’s Manual
Test Commands
Test commands allow to calibrate digital and analog output of the Series it2000
pressure transducer.
TEST:INP
Reads digital counts from selected channels.
Syntax
TEST:INP[channel]?
TEST
Suffix
INP
channel
?
channel
Possible values: 5
Parameter
5
Remarks
:
Result
Digital pressure and temperature counts, Board
temperature
Temperature measurement is the RTD temperature if there is one present,
otherwise it is the temperature from the on-chip temperature sensor.
Board temperature is the temperature from the on-chip temperature sensor
expressed in degrees Celcius.
Example
test:inp5?
11775507,41600,34.5
TEST:OUTPV
Sets analog voltage output corresponding to a given count.
Syntax
TEST:OUTPV count
TEST
Parameters
:
OUTPV
count
Possible values: 0-4095
<Space>
count
Chapter 4: Command Reference
The count is a value which will be send to the digital-to-analog converter to
set the analog output.
Remarks
This command is used to calibrate a transducer’s analog output during the
factory calibration process.
Example
test:outpv 2768
21
22
RS-232 Transducer Digital Communication User’s Manual
System Commands
System commands includes those relating to identification, resetting the unit,
setting a timer.
SYST:VERS:FIRM
Returns the firmware version.
Syntax
SYST:VERS:FIRM?
SYST
Example
:
VERS
:
FIRM
?
syst:vers:firm?
217928G
*IDN
Returns the transducer part number, serial number and a revision.
Syntax
*IDN?
*IDN
Example
?
*idn?
STELLAR TECHNOLOGY INC,IT2000-15A-101,007713,0
*RST
Resets the it2000 to power-up status.
Syntax
*RST
*RST
Remarks
Executing this command is equivalent to executing a power-up sequence.
Example
*rst
Chapter 4: Command Reference
23
OFFSET:SET
Sets or returns the value for the input offset.
Syntax
OFFSET:SET offset
OFFSET:SET?
?
OFFSET
:
SET
<Space>
Parameters
value
offset
Real numeric value.
This signed value will be added to the digital output prior to displaying it.
Input offset will also affect the analog output.
Remarks
Input offset value is always in PSI.
Example
offset:set 3.4
offset:set?
3.40
SPAN:SET
Sets or returns the value for the span.
Syntax
SPAN:SET span
SPAN:SET?
?
SPAN
:
SET
<Space>
Parameters
value
span
Real numeric value from (0..150] interval.
The pressure transducer’s span will be set to the span% of the original value.
Remarks
Default value is 100.
Example
span:set 101
If the pressure transducer has 0-5 V output at 0-100 PSIG, after setting
span=101 analog output will be 0-5.05 V at 0-100 PSIG. Digital output will be
0-101 PSIG.
span:set?
101.00
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RS-232 Transducer Digital Communication User’s Manual
TURNDOWN:SET
Sets or returns the value for the turndown.
TURNDOWN:SET turndown
Syntax
TURNDOWN:SET?
?
TURNDOWN
:
SET
<Space>
Parameters
value
turndown
Real numeric value from [1..100] interval.
The pressure transducer’s pressure range will be set to the turndown% of the
original value.
Remarks
Default value is 100.
Example
turndown:set 50
If the pressure transducer has 0-5 V output at 0-200 PSIG, after setting
turndown=50 output will be 0-5 V at 0-100 PSIG. Digital pressure
measurement is not affected.
turndown:set?
50.000
TIMER:SET
Sets or returns timer settings. The it2000 will send pressure and temperature
readings over a RS-232 in the specified time interval.
TIMER:SET type, value
Syntax
TIMER:SET?
?
TIMER
:
SET
<Space>
Parameters
type
<comma>
type
This value specifies a time interval type.
Possible values: 0-3.
Parameter
0
1
2
3
Result
Interval measured in 1/128 of a second
Interval measured in seconds
Interval measured in minutes
Interval measured in hours
value
Chapter 4: Command Reference
value
Numeric value from 0 to 255.
This value determines a time interval in specified units of measure.
Remarks
Value set to 0 will stop the timer function.
In 1/128 mode not every setting will result in a proper response rate due to the
IT2000 performance limitations.
Example
timer:set 1, 100
timer:set?
sec,100
25
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RS-232 Transducer Digital Communication User’s Manual
Index
Symbols
* (asterisk) 12
: (colon) 12, 13
A
analog output 20, 21, 23
argument 13, 14, 15
Argument Types 14
Block Arguments 15
Numeric Arguments 14
Quoted String Arguments 15
ASCII (American Standard Code for
Information Interchange) 7, 12, 14,
OUTPV 20
Trigger Subsystem
TRIGger
PRESsure 24
Command Usage Rules 16
Commands and Query Structure 12
Commands 13
Queries 13
communication port 10
Communication Setup 7
D
digital
count 20
output 20, 23
pressure 10
temperature 10
digital to analog converter 21
F
firmware 22
15
B
Backus-Naur Form (BNF) 12
Basic Measurements 10
C
carriage-return 7, 14, 16
case
lower 13, 15, 16
upper 13, 15, 16
channel 20
Command Entry 13
Argument Usage 14
Command Termination 14
Suffixes 14
Command Reference 17
Input Subsystem
INPut
OFFSet
VALUE 23
Measure Subsystem 18
MEASure
ALL 19
PRESsure 18
TEMPerature 19
UNIT
PRESsure 19
System Commands 22
*IDN 22
*RST 22
SYSTem
VERSion
FIRMware 22
Test Commands 20
TEST
INPut 20
G
gain 12
L
line-feed 7, 14, 16
M
message 12, 15
mnemonic 12, 13, 14, 16
O
offset
input 23
output
voltage 20
R
RS-232 6, 7, 11
S
Standard Commands for Programmable Instruments (SCPI) 14
suffix 20
Syntax Diagrams 16
W
white space 13, 14
Wiring Harness
RS-232 Connector 6
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RS-232 Transducer Digital Communication User’s Manual
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