HOTLink™ Transmitter/Receiver

fax id: 5004
1CY 7B9 33
CY7B923
CY7B933
HOTLink™ Transmitter/Receiver
Features
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that transfer data over high-speed serial links (fiber, coax, and
twisted pair). Standard HOTLink data rates range from
160-330 Mbits/second. Higher speed HOTLink is also available for high speed applications (160-400 Mbits/second), as
well as for those Low Cost Fiber applications HOTLink-155
(150-160 Mbits/second operations). Figure 1 illustrates typical
connections to host systems or controllers.
Fibre Channel compliant
IBM ESCON® compliant
DVB-ASI compliant
ATM compliant
SMPTE-259M compliant
8B/10B-coded or 10-bit unencoded
Standard HOTLink: 160–330 Mbps
High Speed HOTLink: 160–400 Mbps for high speed applications
Low Speed HOTLink: 150–160 Mbps for Low Cost Fiber
applications
TTL synchronous I/O
No external PLL components
Triple PECL 100K serial outputs
Dual PECL 100K serial inputs
Low power: 350 mW (Tx), 650 mW (Rx)
Compatible with fiber optic modules, coaxial cable, and
twisted pair media
Built-In Self-Test
Single +5V supply
28-pin SOIC/PLCC/LCC
0.8µ BiCMOS
Eight bits of user data or protocol information are loaded into
the HOTLink transmitter and are encoded. Serial data is shifted out of the three differential positive ECL (PECL) serial ports
at the bit rate (which is 10 times the byte rate).
The HOTLink receiver accepts the serial bit stream at its differential line receiver inputs and, using a completely integrated
PLL Clock Synchronizer, recovers the timing information necessary for data reconstruction. The bit stream is deserialized,
decoded, and checked for transmission errors. Recovered
bytes are presented in parallel to the receiving host along with
a byte rate clock.
The 8B/10B encoder/decoder can be disabled in systems that
already encode or scramble the transmitted data. I/O signals
are available to create a seamless interface with both asynchronous FIFOs (i.e., CY7C42X) and clocked FIFOs (i.e.,
CY7C44X). A Built-In Self-Test pattern generator and checker
allows testing of the transmitter, receiver, and the connecting
link as a part of a system diagnostic check.
HOTLink devices are ideal for a variety of applications where
a parallel interface can be replaced with a high-speed
point-to-point serial link. Applications include interconnecting
workstations, servers, mass storage, and video transmission
equipment.
Functional Description
The CY7B923 HOTLink™ Transmitter and CY7B933 HOTLink
Receiver are point-to-point communications building blocks
CY7B923 Transmitter Logic Block Diagram
CY7B933 Receiver Logic Block Diagram
SC/D (Da)
D0− 7
(Db − h)
RP ENN
ENA
RF
SVS(Dj)
FOTO
ENABLE
INPUT REGISTER
CKW
FRAMER
A/B
INA+
INA−
DATA
INB (INB+)
SI(INB− )
PECL
TTL
ENCODER
SO
CLOCK
GENERATOR
OUTA
SHIFTER
OUTB
OUTC
MODE
BISTEN
TEST
LOGIC
SHIFTER
DECODER
REGISTER
CLOCK
SYNC
DECODER
REFCLK
MODE
OUTPUT
REGISTER
TEST
LOGIC
BISTEN
B923–1
CKR
RDY
Q0− 7
(Qb − h)
RVS(Qj)
SC/D (Qa) B923–2
HOTLink is a trademark of cypress Semiconductor Corporation.
ESCON is a registered trademark of IBM.
Cypress Semiconductor Corporation
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3901 North First Street
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San Jose
• CA 95134 •
408-943-2600
December 1991 – Revised August 14, 1997
PROTOCOL
LOGIC
RECEIVE
MESSAGE
BUFFER
7B933
RECEIVER
7B923
TRANSMITTER
TRANSMIT
MESSAGE
BUFFER
PROTOCOL
LOGIC
CY7B923
CY7B933
SERIAL LINK
HOST
HOST
B923–3
Figure 1. HOTLink System Connections
CY7B923 Transmitter Pin Configurations
CY7B933 Receiver Pin Configurations
SOIC
Top View
SOIC
Top View
OUTB−
OUTC−
OUTC+
VCCN
BISTEN
GND
MODE
RP
VCCQ
SVS(D j)
(Dh) D7
(Dg)D 6
(Df)D 5
(Di)D 4
1
2
27
3
26
4
25
5
24
6
23
7
22
7B923
8
21
9
20
10
19
11
18
12
17
13
16
14
15
INA−
INA+
A/B
BISTEN
RF
GND
RDY
GND
VCCN
RVS (Qj)
(Qh) Q7
(Qg) Q6
(Qf) Q5
(Qi) Q4
OUTB+
OUTA+
OUTA−
FOTO
ENN
ENA
VCCQ
CKW
GND
SC/D(D a)
D0 (Db)
D1 (Dc)
D2 (Dd)
D3 (De)
28
1
28
2
27
3
26
4
25
5
24
6
23
7
8
7B933
INB(INB+)
SI(INB− )
MODE
REFCLK
VCCQ
SO
CKR
VCCQ
GND
SC/D (Qa)
Q0 (Qb)
Q1 (Qc)
Q2 (Qd)
Q3 (Qe)
22
21
9
20
10
19
11
18
12
17
13
16
14
15
B923–7
B923–5
PLCC/LCC
Top View
VCCN
OUTC+
OUTC−
OUTB−
OUTB+
OUTA+
OUTA−
BISTEN
A/B
INA+
INA−
INB (INB+)
SI (INB−)
MODE
PLCC/LCC
Top View
4 3 2 1 28 2726
25
24
23
22
21
20
19
FOTO
ENN
ENA
VCCQ
CKW
GND
SC/D(D a)
4 3 2 1 28 2726
RF
GND
RDY
GND
VCCN
RVS (Qj)
(Qh) Q7
B923–4
5
6
7
7B933
8
9
10
11 1213 14 15 16 1718
25
24
23
22
21
20
19
(Qg ) Q 6
(Q f ) Q 5
(Q i ) Q 4
(Q e ) Q 3
(Qd ) Q 2
(Q c ) Q 1
(Qb ) Q 0
5
6
7
7B923
8
9
10
11 1213 14 15 16 1718
(Dg ) D 6
(D f ) D 5
(D i ) D 4
(D e ) D 3
(Dd ) D 2
(D c ) D 1
(Db ) D 0
BISTEN
GND
MODE
RP
VCCQ
SVS(D j)
(Dh)D 7
2
REFCLK
VCCQ
SO
CKR
VCCQ
GND
SC/D (Qa)
B923–6
CY7B923
CY7B933
Maximum Ratings
(Above which the useful life may be impaired. For user guidelines, not tested.)
Static Discharge Voltage ........................................... >4001V
(per MIL−STD−883, Method 3015)
Storage Temperature ......................................− 65°C to +150°C
Latch-Up Current ..................................................... >200 mA
Ambient Temperature with
Power Applied..................................................− 55°C to +125°C
Operating Range
Supply Voltage to Ground Potential ................ − 0.5V to +7.0V
Range
DC Input Voltage ................................................ − 0.5V to +7.0V
Commercial
Output Current into TTL Outputs (LOW)...................... 30 mA
Industrial
Output Current into PECL outputs (HIGH) ...................−50 mA
Military
Ambient
Temperature
VCC
0°C to +70°C
5V ± 10%
−40°C to +85°C
5V ± 10%
−55°C to +125°C
Case Temperature
5V ± 10%
Pin Descriptions
CY7B923 HOTLink Transmitter
Name
I/O
Description
D0−7
(Db − h)
TTL In
Parallel Data Input. Data is clocked into the Transmitter on the rising edge of CKW if ENA is LOW
(or on the next rising CKW with ENN LOW). If ENA and ENN are HIGH, a Null character (K28.5) is
sent. When MODE is HIGH, D0, 1, ...7 become Db, c,...h respectively.
SC/D (Da)
TTL In
Special Character/Data Select. A HIGH on SC/D when CKW rises causes the transmitter to encode
the pattern on D0−7 as a control code (Special Character), while a LOW causes the data to be coded
using the 8B/10B data alphabet. When MODE is HIGH, SC/D (Da) acts as Da input. SC/D has the
same timing as D0−7.
SVS
(Dj)
TTL In
Send Violation Symbol. If SVS is HIGH when CKW rises, a Violation symbol is encoded and sent
while the data on the parallel inputs is ignored. If SVS is LOW, the state of D0−7 and SC/D determines
the code sent. In normal or test mode, this pin overrides the BIST generator and forces the transmission of a Violation code. When MODE is HIGH (placing the transmitter in unencoded mode),
SVS (Dj) acts as the Dj input. SVS has the same timing as D0−7.
ENA
TTL In
Enable Parallel Data. If ENA is LOW on the rising edge of CKW, the data is loaded, encoded, and
sent. If ENA and ENN are HIGH, the data inputs are ignored and the Transmitter will insert a Null
character (K28.5) to fill the space between user data. ENA may be held HIGH/LOW continuously or
it may be pulsed with each data byte to be sent. If ENA is being used for data control, ENN will
normally be strapped HIGH, but can be used for BIST function control.
ENN
TTL In
Enable Next Parallel Data. If ENN is LOW, the data appearing on D0−7 at the next rising edge of
CKW is loaded, encoded, and sent. If ENA and ENN are HIGH, the data appearing on D0−7 at the
next rising edge of CKW will be ignored and the Transmitter will insert a Null character to fill the space
between user data. ENN may be held HIGH/LOW continuously or it may be pulsed with each data
byte sent. If ENN is being used for data control, ENA will normally be strapped HIGH, but can be
used for BIST function control.
CKW
TTL In
Clock Write. CKW is both the clock frequency reference for the multiplying PLL that generates the
high−speed transmit clock, and the byte rate write signal that synchronizes the parallel data input.
CKW must be connected to a crystal controlled time base that runs within the specified frequency
range of the Transmitter and Receiver.
FOTO
TTL In
Fiber Optic Transmitter Off. FOTO determines the function of two of the three PECL transmitter
output pairs. If FOTO is LOW, the data encoded by the Transmitter will appear at the outputs
continuously. If FOTO is HIGH, OUTA± and OUTB± are forced to their “logic zero” state (OUT+ =
LOW and OUT− = HIGH), causing a fiber optic transmit module to extinguish its light output. OUTC
is unaffected by the level on FOTO, and can be used as a loop-back signal source for board-level
diagnostic testing.
3
CY7B923
CY7B933
CY7B923 HOTLink Transmitter (continued)
Name
I/O
Description
OUT A±
OUT B±
OUT C±
PECL Out
Differential Serial Data Outputs. These PECL 100K outputs (+5V referenced) are capable of driving
terminated transmission lines or commercial fiber optic transmitter modules. Unused pairs of outputs
can be wired to VCC to reduce power if the output is not required. OUTA± and OUTB± are controlled by
the level on FOTO, and will remain at their “logical zero” states when FOTO is asserted. OUTC± is unaffected
by the level on FOTO. (OUTA+ and OUTB+ are used as a differential test clock input while in Test mode,
i.e., MODE=UNCONNECTED or forced to VCC/2.)
MODE
3-Level In
Encoder Mode Select. The level on MODE determines the encoding method to be used. When
wired to GND, MODE selects 8B/10B encoding. When wired to VCC, data inputs bypass the encoder
and the bit pattern on Da-j goes directly to the shifter. When left floating (internal resistors hold the input at
VCC/2) the internal bit-clock generator is disabled and OUTA+/OUTB+ become the differential bit clock to be
used for factory test. In typical applications MODE is wired to VCC or GND.
BISTEN
TTL In
Built-In Self-Test Enable. When BISTEN is LOW and ENA and ENN are HIGH, the transmitter sends an
alternating 1−0 pattern (D10.2 or D21.5). When either ENA or ENN is set LOW and BISTEN is LOW, the
transmitter begins a repeating test sequence that allows the Transmitter and Receiver to work together to
test the function of the entire link. In normal use this input is held HIGH or wired to VCC. The BIST generator
is a free-running pattern generator that need not be initialized, but if required, the BIST sequence can be
initialized by momentarily asserting SVS while BISTEN is LOW. BISTEN has the same timing as D0−7.
RP
TTL Out
Read Pulse. RP is a 60% LOW duty-cycle byte-rate pulse train suitable for the read pulse in CY7C42X
FIFOs. The frequency on RP is the same as CKW when enabled by ENA, and duty cycle is independent of
the CKW duty cycle. Pulse widths are set by logic internal to the transmitter. In BIST mode, RP will remain
HIGH for all but the last byte of a test loop. RP will pulse LOW one byte time per BIST loop.
VCCN
Power for output drivers.
VCCQ
Power for internal circuitry.
GND
Ground.
CY7B933 HOTLink Receiver
Name
I/O
Description
Q 0−7
(Qb − h)
TTL Out
Q 0−7 Parallel Data Output. Q0−7 contain the most recently received data. These outputs change synchronously with CKR. When MODE is HIGH, Q0, 1, ...7 become Qb, c,...h respectively.
SC/D(Qa)
TTL Out
Special Character/Data Select. SC/D indicates the context of received data. HIGH indicates a Control
(Special Character) code, LOW indicates a Data character. When MODE is HIGH (placing the receiver in
Unencoded mode), SC/D acts as the Qa output. SC/D has the same timing as Q0−7.
RVS (Qj)
TTL Out
Received Violation Symbol. A HIGH on RVS indicates that a code rule violation has been detected
in the received data stream. A LOW shows that no error has been detected. In BIST mode, a LOW
on RVS indicates correct operation of the Transmitter, Receiver, and link on a byte-by-byte basis.
When MODE is HIGH (placing the receiver in Unencoded mode), RVS acts as the Qj output. RVS has
the same timing as Q0−7.
RDY
TTL Out
Data Output Ready. A LOW pulse on RDY indicates that new data has been received and is ready to be
delivered. A missing pulse on RDY shows that the received data is the Null character (normally inserted by
the transmitter as a pad between data inputs). In BIST mode RDY will remain LOW for all but the last byte
of a test loop and will pulse HIGH one byte time per BIST loop.
CKR
TTL Out
Clock Read. This byte rate clock output is phase and frequency aligned to the incoming serial data
stream. RDY, Q0−7, SC/D, and RVS all switch synchronously with the rising edge of this output.
A/B
PECL in
Serial Data Input Select. This PECL 100K (+5V referenced) input selects INA or INB as the active
data input. If A/B is HIGH, INA is connected to the shifter and signals connected to INA will be decoded. If
A/B is LOW INB is selected.
INA±
Diff In
Serial Data Input A. The differential signal at the receiver end of the communication link may be
connected to the differential input pairs INA± or INB±. Either the INA pair or the INB pair can be used as
the main data input and the other can be used as a loopback channel or as an alternative data input selected
by the state of A/B.
4
CY7B923
CY7B933
CY7B933 HOTLink Receiver (continued)
Name
I/O
Description
INB
(INB+)
PECL in
(Diff In)
Serial Data Input B. This pin is either a single-ended PECL data receiver (INB) or half of the INB
differential pair. If SO is wired to VCC, then INB± can be used as differential line receiver interchangeably
with INA±. If SO is normally connected and loaded, INB becomes a single-ended PECL 100K (+5V referenced) serial data input. INB is used as the test clock while in Test mode.
SI
(INB−)
PECL in
(Diff In)
Status Input. This pin is either a single-ended PECL status monitor input (SI) or half of the INB
differential pair. If SO is wired to VCC, then INB± can be used as differential line receiver interchangeably
with INA±. If SO is normally connected and loaded, SI becomes a single-ended PECL 100K (+5V referenced)
status monitor input, which is translated into a TTL-level signal at the SO pin.
SO
TTL Out
Status Out. SO is the TTL-translated output of SI. It is typically used to translate the Carrier Detect
output from a fiber-optic receiver connected to SI. When this pin is normally connected and loaded
(without any external pull-up resistor), SO will assume the same logical level as SI and INB will
become a single-ended PECL serial data input. If the status monitor translation is not desired, then
SO may be wired to VCC and the INB± pair may be used as a differential serial data input.
RF
TTL In
Reframe Enable. RF controls the Framer logic in the Receiver. When RF is held HIGH, each SYNC
(K28.5) symbol detected in the shifter will frame the data that follows. If is HIGH for 2,048 consecutive
bytes, the internal framer switches to double-byte mode. When RF is held LOW, the reframing logic
is disabled. The incoming data stream is then continuously deserialized and decoded using byte
boundaries set by the internal byte counter. Bit errors in the data stream will not cause alias SYNC
characters to reframe the data erroneously.
REFCLK
TTL In
Reference Clock. REFCLK is the clock frequency reference for the clock/data synchronizing PLL.
REFCLK sets the approximate center frequency for the internal PLL to track the incoming bit stream.
REFCLK must be connected to a crystal-controlled time base that runs within the frequency limits of
the Tx/Rx pair, and the frequency must be the same as the transmitter CKW frequency (within
CKW±0.1%)
MODE
3-Level In
Decoder Mode Select. The level on the MODE pin determines the decoding method to be used.
When wired to GND, MODE selects 8B/10B decoding. When wired to VCC, registered shifter contents
bypass the decoder and are sent to Qa−j directly. When left floating (internal resistors hold the MODE pin at
VCC/2) the internal bit clock generator is disabled and INB becomes the bit rate test clock to be used for factory
test. In typical applications, MODE is wired to VCC or GND.
BISTEN
TTL In
Built-In Self-Test Enable. When BISTEN is LOW the Receiver awaits a D0.0 (sent once per BIST loop)
character and begins a continuous test sequence that tests the functionality of the Transmitter, the Receiver,
and the link connecting them. In BIST mode the status of the test can be monitored with RDY and RVS
outputs. In normal use BISTEN is held HIGH or wired to VCC. BISTEN has the same timing as Q0−7.
VCCN
Power for output drivers.
VCCQ
Power for internal circuitry.
GND
Ground.
In BIST mode, the Input register becomes the signature pattern generator by logically converting the parallel Input register
into a Linear Feedback Shift Register (LFSR). When enabled,
this LFSR will generate a 511-byte sequence that includes all
Data and Special Character codes, including the explicit violation symbols. This pattern provides a predictable but pseudo-random sequence that can be matched to an identical
LFSR in the Receiver.
CY7B923 HOTLink Transmitter Block Diagram
Description
Input Register
The Input register holds the data to be processed by the HOTLink transmitter and allows the input timing to be made consistent with standard FIFOs. The Input register is clocked by
CKW and loaded with information on the D0−7, SC/D, and SVS
pins. Two enable inputs (ENA and ENN) allow the user to choose
when data is loaded in the register. Asserting ENA (Enable, active
LOW) causes the inputs to be loaded in the register on the rising
edge of CKW. If ENN (Enable Next, active LOW) is asserted when
CKW rises, the data present on the inputs on the next rising edge
of CKW will be loaded into the Input register. If neither ENA nor ENN
are asserted LOW on the rising edge of CKW, then a SYNC (K28.5)
character is sent. These two inputs allow proper timing and function
for compatibility with either asynchronous FIFOs or clocked FIFOs
without external logic, as shown in Figure 5.
Encoder
The Encoder transforms the input data held by the Input register into a form more suitable for transmission on a serial interface link. The code used is specified by ANSI X3.230 (Fibre
Channel) and the IBM ESCON channel (code tables are at the
end of this datasheet). The eight D0−7 data inputs are converted
to either a Data symbol or a Special Character, depending upon the
state of the SC/D input. If SC/D is HIGH, the data inputs represent
a control code and are encoded using the Special Character code
5
CY7B923
CY7B933
table. If SC/D is LOW, the data inputs are converted using the Data
code table. If a byte time passes with the inputs disabled, the Encoder will output a Special Character Comma K28.5 (or SYNC) that
will maintain link synchronization. SVS input forces the transmission of a specified Violation symbol to allow the user to check error
handling system logic in the controller or for proprietary applications.
pulse stream will insure correct data transfers between asynchronous FIFOs and the transmitter input latch with no external logic.
Test Logic
Test logic includes the initialization and control for the Built-In
Self-Test (BIST) generator, the multiplexer for Test mode clock
distribution, and control logic to properly select the data encoding. Test logic is discussed in more detail in the CY7B923
HOTLink Transmitter Operating Mode Description.
The 8B/10B coding function of the Encoder can be bypassed
for systems that include an external coder or scrambler function as part of the controller. This bypass is controlled by setting the MODE select pin HIGH. When in bypass mode, D a−j
(note that bit order is specified in the Fibre Channel 8B/10B code)
become the ten inputs to the Shifter, with Da being the first bit to be
shifted out.
CY7B933 HOTLink Receiver Block Diagram
Description
Serial Data Inputs
Shifter
Two pairs of differential line receivers are the inputs for the
serial data stream. INA± or INB± can be selected with the A/B
input. INA± is selected with A/B HIGH and INB± is selected with A/B
LOW. The threshold of A/B is compatible with the ECL 100K signals
from PECL fiber optic interface modules. TTL logic elements can be
used to select the A or B inputs by adding a resistor pull-up to the
TTL driver connected to A/B. The differential threshold of INA± and
INB± will accommodate wire interconnect with filtering losses or
transmission line attenuation greater than 20 db (VDIF > 50 mv) or
can be directly connected to fiber optic interface modules (any ECL
logic family, not limited to ECL 100K). The common mode tolerance
will accommodate a wide range of signal termination voltages. The
highest HIGH input that can be tolerated is VIN = VCC, and the
lowest LOW input that can be interpreted correctly is VIN =
GND+2.0V.
The Shifter accepts parallel data from the Encoder once each
byte time and shifts it to the serial interface output buffers using a PLL multiplied bit clock that runs at ten (10) times the
byte clock rate. Timing for the parallel transfer is controlled by
the counter included in the Clock Generator and is not affected
by signal levels or timing at the input pins.
OutA, OutB, OutC
The serial interface PECL output buffers (ECL100K referenced to +5V) are the drivers for the serial media. They are all
connected to the Shifter and contain the same serial data. Two
of the output pairs (OUTA± and OUTB±) are controllable by the
FOTO input and can be disabled by the system controller to force a
logical zero (i.e., “light off”) at the outputs. The third output pair
(OUTC±) is not affected by FOTO and will supply a continuous data
stream suitable for loop-back testing of the subsystem.
PECL-TTL Translator
The function of the INB(INB+) input and the SI(INB−) input is
defined by the connections on the SO output pin. If the
PECL/TTL translator function is not required, the SO output is
wired to VCC. A sensor circuit will detect this connection and
cause the inputs to become INB± (a differential line-receiver serial-data input). If the PECL/TTL translator function is required, the
SO output is connected to its normal TTL load (typically one or more
TTL inputs, but no pull-up resistor) and the INB+ input becomes INB
(single-ended ECL 100K, serial data input) and the INB− input becomes SI (single-ended, ECL 100K status input).
OUTA± and OUTB± will respond to FOTO input changes within a
few bit times. However, since FOTO is not synchronized with the
transmitter data stream, the outputs will be forced off or turned on
at arbitrary points in a transmitted byte. This function is intended to
augment an external laser safety controller and as an aid for Receiver PLL testing.
In wire-based systems, control of the outputs may not be required, and FOTO can be strapped LOW. The three outputs
are intended to add system and architectural flexibility by offering identical serial bit streams with separate interfaces for
redundant connections or for multiple destinations. Unneeded
outputs can be wired to VCC to disable and power down the
unused output circuitry.
This positive-referenced PECL-to-TTL translator is provided to
eliminate external logic between an PECL fiber-optic interface
module “carrier detect” output and the TTL input in the control
logic. The input threshold is compatible with ECL 100K levels
(+5V referenced). It can also be used as part of the link status
indication logic for wire connected systems.
Clock Generator
The clock generator is an embedded phase-locked loop (PLL)
that takes a byte-rate reference clock (CKW) and multiplies it
by ten (10) to create a bit rate clock for driving the serial shifter.
The byte rate reference comes from CKW, the rising edge of
which clocks data into the Input register. This clock must be a
crystal referenced pulse stream that has a frequency between
the minimum and maximum specified for the HOTLink Transmitter/Receiver pair. Signals controlled by this block form the
bit clock and the timing signals that control internal data transfers between the Input register and the Shifter.
Clock Synchronization
The Clock Synchronization function is performed by an embedded phase-locked loop (PLL) that tracks the frequency of
the incoming bit stream and aligns the phase of its internal bit
rate clock to the serial data transitions. This block contains the
logic to transfer the data from the Shifter to the Decode register
once every byte. The counter that controls this transfer is initialized by the Framer logic. CKR is a buffered output derived
from the bit counter used to control the Decode register and
the output register transfers.
The read pulse (RP) is derived from the feedback counter used in
the PLL multiplier. It is a byte-rate pulse stream with the proper
phase and pulse widths to allow transfer of data from an asynchronous FIFO. Pulse width is independent of CKW duty cycle, since
proper phase and duty cycle is maintained by the PLL. The RP
Clock output logic is designed so that when reframing causes
the counter sequence to be interrupted, the period and pulse
width of CKR will never be less than normal. Reframing may
stretch the period of CKR by up to 90%, and either CKR Pulse
6
CY7B923
CY7B933
Decoder
Width HIGH or Pulse Width LOW may be stretched, depending on when reframe occurs.
Parallel data is transformed from ANSI-specified X3.230
8B/10B codes back to “raw data” in the Decoder. This block
uses the standard decoder patterns shown in the Valid Data
Characters and Valid Special Character Codes and Sequences sections of this datasheet. Data patterns are signaled by a
LOW on the SC/D output and Special Character patterns are signaled by a HIGH on the SC/D output. Unused patterns or disparity
errors are signaled as errors by a HIGH on the RVS output and by
specific Special Character codes.
The REFCLK input provides a byte-rate reference frequency
to improve PLL acquisition time and limit unlocked frequency
excursions of the CKR when no data is present at the serial
inputs. The frequency of REFCLK is required to be within
±0.1% of the frequency of the clock that drives the transmitter
CKW pin.
Framer
Framer logic checks the incoming bit stream for the pattern
that defines the byte boundaries. This combinatorial logic filter
looks for the X3.230 symbol defined as a Special Character
Comma (K28.5). When it is found, the free-running bit counter
in the Clock Synchronization block is synchronously reset to
its initial state, thus framing the data correctly on the correct
byte boundaries.
Output Register
The Output register holds the recovered data (Q0−7, SC/D, and
RVS) and aligns it with the recovered byte clock (CKR). This synchronization insures proper timing to match a FIFO interface or other logic that requires glitch free and specified output behavior. Outputs change synchronously with the rising edge of CKR.
Random errors that occur in the serial data can corrupt some
data patterns into a bit pattern identical to a K28.5, and thus
cause an erroneous data-framing error. The RF input prevents
this by inhibiting reframing during times when normal message
data is present. When RF is held LOW, the HOTLink receiver
will deserialize the incoming data without trying to reframe the
data to incoming patterns. When RF rises, RDY will be inhibited
until a K28.5 has been detected, after which RDY will resume its
normal function. While RF is HIGH, it is possible that an error could
cause misframing, after which all data will be corrupted. Likewise,
a K28.7 followed by D11.x, D20.x, or an SVS (C0.7) followed by
D11.x will create alias K28.5 characters and cause erroneous framing. These sequences must be avoided while RF is HIGH.
In BIST mode, this register becomes the signature pattern
generator and checker by logically converting itself into a Linear Feedback Shift Register (LFSR) pattern generator. When
enabled, this LFSR will generate a 511-byte sequence that
includes all Data and Special Character codes, including the
explicit violation symbols. This pattern provides a predictable
but pseudo-random sequence that can be matched to an identical LFSR in the Transmitter. When synchronized, it checks
each byte in the Decoder with each byte generated by the
LFSR and shows errors at RVS. Patterns generated by the
LFSR are compared after being buffered to the output pins and
then fed back to the comparators, allowing test of the entire
receive function.
If RF remains HIGH for greater than 2048 bytes, the framer
converts to double-byte framing, requiring two K28.5 characters aligned on the same byte boundary within 5 bytes in order
to reframe. Double-byte framing greatly reduces the possibility of erroneously reframing to an aliased K28.5 character.
In BIST mode, the LFSR is initialized by the first occurrence of
the transmitter BIST loop start code D0.0 (D0.0 is sent only
once per BIST loop). Once the BIST loop has been started,
RVS will be HIGH for pattern mismatches between the received sequence and the internally generated sequence.
Code rule violations or running disparity errors that occur as
part of the BIST loop will not cause an error indication. RDY
will pulse HIGH once per BIST loop and can be used to check test
pattern progress. The receiver BIST generator can be reinitialized
by leaving and re-entering BIST mode.
Shifter
The Shifter accepts serial inputs from the Serial Data inputs
one bit at a time, as clocked by the Clock Synchronization
logic. Data is transferred to the Framer on each bit, and to the
Decode register once per byte.
Test Logic
Decode Register
Test logic includes the initialization and control for the Built-In
Self-Test (BIST) generator, the multiplexer for Test mode clock
distribution, and control logic for the decoder. Test logic is discussed in more detail in the CY7B933 HOTLink Receiver Operating Mode Description
The Decode register accepts data from the Shifter once per
byte as determined by the logic in the Clock Synchronization
block. It is presented to the Decoder and held until it is transferred to the output latch.
7
CY7B923
CY7B933
CY7B923/CY7B933 Electrical Characteristics Over the Operating Range[1]
Parameter
Description
Test Conditions
Min.
Max.
Unit
TTL OUTs, CY7B923: RP; CY7B933: Q0−7, SC/D, RVS, RDY, CKR, SO
VOHT
Output HIGH Voltage
IOH = − 2 mA
VOLT
Output LOW Voltage
IOL = 4 mA
IOST
Output Short Circuit Current
VOUT =0V[2]
2.4
V
0.45
V
− 90
mA
2.0
VCC
V
2.2
VCC
V
−0.5
0.8
V
−15
TTL INs, CY7B923: D0−7, SC/D, SVS, ENA, ENN, CKW, FOTO, BISTEN; CY7B933: RF, REFCLK, BISTEN
VIHT
Input HIGH Voltage
Com’l, Ind’l, & Mil
VILT
Input LOW Voltage
IIHT
Input HIGH Current
VIN = VCC
IILT
Input LOW Current
VIN = 0.0V
Ind’l & Mil (CKW and FOTO, only)
−10
+10
µA
− 500
µA
Transmitter PECL-Compatible Output Pins: OUTA+, OUTA−, OUTB+, OUTB−, OUTC+, OUTC−
VOHE
VOLE
VODIF
Output HIGH Voltage
(VCC referenced)
Load = 50Ω to Com’l
VCC − 2V
Ind’l & Mil
VCC−1.03
VCC−0.83
V
VCC−1.05
VCC−0.83
V
Output LOW Voltage
(VCC referenced)
Load = 50Ω to Com’l
VCC − 2V
Ind’l & Mil
VCC−1.86
VCC−1.62
V
VCC−1.96
VCC−1.62
V
Output Differential Voltage
|(OUT+) − (OUT−)|
Load = 50 ohms to VCC − 2V
0.6
V
Receiver PECL-Compatible Input Pins: A/B, SI, INB
VIHE
VILE
Input HIGH Voltage
Input LOW Voltage
IIHE[3]
IILE[3]
Input HIGH Current
VIN = VIHE Max.
Input LOW Current
VIN = VILE Min.
Com’l
VCC−1.165
VCC
V
Ind’l & Mil
VCC−1.14
VCC
V
Com’l
2.0
VCC−1.475
V
Ind’l & Mil
2.0
VCC−1.50
V
+500
µA
+0.5
µA
50
mV
Differential Line Receiver Input Pins: INA+, INA−, INB+, INB−
VDIFF
Input Differential Voltage
|(IN+) − (IN−)|
VIHH
Highest Input HIGH Voltage
VILL
Lowest Input LOW Voltage
IIHH
Input HIGH Current
VIN = VIHH Max.
IILL[4]
Input LOW Current
VIN = VILL Min.
VCC
2.0
ICCT[5]
ICCR[6]
Transmitter Power Supply
Current
Freq. = Max.
Receiver Power Supply
Current
Freq. = Max.
V
750
−200
Miscellaneous
V
µA
µA
Typ.
Max.
Com’l
65
85
mA
Ind’l & Mil
75
95
mA
Com’l
120
155
mA
Ind’l & Mil
135
160
mA
Notes:
1. See the last page of this specification for Group A subgroup testing information.
2. Tested one output at a time, output shorted for less than one second, less than 10% duty cycle.
3. Applies to A/B only.
4. Input currents are always positive at all voltages above VCC/2.
5. Maximum ICCT is measured with VCC = Max., one PECL output pair loaded with 50 ohms to VCC − 2.0V, and other PECL outputs tied to VCC. Typical ICCT is measured with
VCC = 5.0V, TA = 25°C, one output pair loaded with 50 ohms to VCC − 2.0V, others tied to VCC, BISTEN = LOW. ICCT includes current into VCCQ (pin 9 and pin 22) only. Current
into VCCN is determined by PECL load currents, typically 30 mA with 50 ohms to VCC − 2.0V. Each additional enabled PECL pair adds 5 mA to ICCT and an additional load
current to VCCN as described. When calculating the contribution of PECL load currents to chip power dissipation, the output load current should be multiplied by 1V instead of VCC.
6. Maximum I CCR is measured with VCC = Max., RF = LOW, and outputs unloaded. Typical ICCR is measured with VCC = 5.0V, TA = 25°C, RF = LOW, BISTEN = LOW, and
outputs unloaded. ICCR includes current into VCCQ (pins 21 and 24). Current into VCCN (pin 9) is determined by the total TTL output buffer quiescent current plus the sum of all
the load currents for each output pin. The total buffer quiescent current is 10mA max., and max. TTL load current for each output pin can be calculated as follows: Where
I I CCN
+
TTLPin
0.95) (VCCN * 5)*0.3
) CL *
RL
VCCN
) 1.5 * Fpin * 1.1
2
RL=equivalent load resistance, CL=capacitive load, and Fpin=frequency in MHz of data on pin. A derating factor of 1.1 has been included to account for worst
process corner and temperature condition.
8
CY7B923
CY7B933
Capacitance[7]
Parameter
CIN
Description
Test Conditions
Input Capacitance
TA = 25°C, f0 = 1 MHz, VCC = 5.0V
Max.
Unit
10
pF
AC Test Loads and Waveforms
5V
R1
OUTPUT
R1=910 Ω
R2=510 Ω
CL < 30 pF
(Includes fixture and
probe capacitance)
VCC − 2
CL
CL
RL =50 Ω
CL < 5 pF
(Includes fixture and
probe capacitance)
RL
R2
(a) TTL AC Test Load
[8]
[8]
(b) PECL AC Test Load
B923–8
3.0V
VIHE
3.0V
2.0V
GND
VIHE
2.0V
1.0V
80%
1.0V
< 1 ns
VILE
< 1 ns
80%
20%
20%
VILE
< 1 ns
< 1 ns
B923–10
B923–9
(c) TTL Input Test Waveform
(d) PECL Input Test Waveform
Transmitter Switching Characteristics Over the Operating Range[1]
7B923-155
Parameter
Description
7B923
7B923-400
Min.
Max
Min.
Max
Min.
Max
Unit
tCKW
Write Clock Cycle
62.5
66.7
30.3
62.5
25
62.5
ns
tB
Bit Time[9]
6.25
6.67
3.03
6.25
2.5
6.25
ns
tCPWH
CKW Pulse Width HIGH
6.5
6.5
6.5
ns
tCPWL
CKW Pulse Width LOW
6.5
6.5
6.5
ns
5
5
5
ns
0
0
0
ns
6tB + 8
6tB + 8
6tB + 8
ns
0
0
0
ns
Time[10]
tSD
Data Set-Up
tHD
Data Hold Time[10]
tSENP
tHENP
Enable Set-Up Time (to insure correct
Enable Hold Time (to insure correct
Read Pulse Rise
tPPWH
Read Pulse HIGH[12]
tRISE
Read Pulse Fall
RP)[11]
Alignment[12]
PECL Output Rise Time 20−80% (PECL Test
−4
2
−4
2
ns
4tB−3
4tB−3
ns
6tB−3
6tB−3
6tB−3
ns
1.2
1.2
ns
1.2
1.2
1.2
ns
35
35
35
ps
Random Jitter
(peak-peak) [7,14]
175
175
175
ps
Random Jitter
(σ)[7,14]
20
20
20
ps
PECL Output Fall Time 80−20% (PECL Test
tDJ
Deterministic Jitter (peak-peak)[7,13]
tRJ
Load)[7]
2
4tB−3
1.2
tFALL
tRJ
−4
Alignment[12]
tPDR
tPDF
RP)[11]
Load)[7]
Notes:
7. Tested initially and after any design or process changes that may affect these parameters, but not 100% tested.
8. Cypress uses constant current (ATE) load configurations and forcing functions. This figure is for reference only.
9. Transmitter tB is calculated as tCKW/10. The byte rate is one tenth of the bit rate.
10. Data includes D0−7, SC/D, SVS, ENA, ENN, and BISTEN. tSD and tHD minimum timing assures correct data load on rising edge of CKW, but not RP function or timing.
11. tSENP and tHENP timing insures correct RP function and correct data load on the rising edge of CKW.
12. Loading on RP is the standard TTL test load shown in part (a) of AC Test Loads and Waveforms except CL = 15 pF.
13. While sending continuous K28.5s, RP unloaded, outputs loaded to 50Ω to VCC−2.0V, over the operating range.
14. While sending continuous K28.7s, after 100,000 samples measured at the cross point of differential outputs, time referenced to CKW input, over the operating
range.
9
CY7B923
CY7B933
Receiver Switching Characteristics Over the Operating Range[1]
7B933-155
Parameter
7B933
7B933-400
Description
Min.
Max
Min.
Max.
Min.
Max.
Unit
tCKR
Read Clock Period (No Serial Data Input), REFCLK
as Reference[15]
−1
+1
−1
+1
−1
+1
%
tB
Bit Time[16]
6.25
6.67
3.03
6.25
2.5
6.25
ns
tCPRH
Read Clock Pulse HIGH
5tB−3
5tB−3
5tB−3
ns
tCPRL
Read Clock Pulse LOW
5tB−3
5tB−3
5tB−3
ns
tRH
RDY Hold Time
tB−2.5
tB−2.5
tB−2.5
ns
tPRF
RDY Pulse Fall to CKR Rise
5tB−3
5tB−3
5tB−3
ns
tPRH
RDY Pulse Width HIGH
4tB−3
4tB−3
4tB−3
ns
Time[17, 18]
2tB−2
tA
Data Access
tROH
Data Hold Time[17, 18]
[17, 18]
2tB+
4
2tB−2
2tB+4
2tB−2
2tB+4
ns
tB−2.5
tB−2.5
tB−2.5
ns
2tB−3
2tB−3
2tB−3
ns
tH
Data Hold Time from CKR Rise
tCKX
REFCLK Clock Period Referenced to CKW of
Transmitter[19]
−0.1
tCPXH
REFCLK Clock Pulse HIGH
6.5
6.5
6.5
ns
tCPXL
REFCLK Clock Pulse LOW
6.5
6.5
6.5
ns
tDS
Propagation Delay SI to SO (note PECL and TTL
thresholds)[20]
20
20
20
ns
tSA
Static Alignment[7, 21]
100
100
100
ps
tEFW
Error Free
Window[7, 22]
0.9tB
+0.1
−0.1
0.9tB
+0.1
−0.1
+0.1
%
0.9tB
Notes:
15. The period of tCKR will match the period of the transmitter CKW when the receiver is receiving serial data. When data is interrupted, CKR may drift to one of the range limits
above.
16. Receiver tB is calculated as tCKR/10 if no data is being received, or tCKW/10 if data is being received. See note.
17. Data includes Q0−7, SC/D, and RVS.
18. tA, tROH, and tH specifications are only valid if all outputs (CKR, RDY, Q0−7, SC/D, and RVS) are loaded with similar DC and AC loads.
19. REFCLK has no phase or frequency relationship with CKR and only acts as a centering reference to reduce clock synchronization time. REFCLK must be
within 0.1% of the transmitter CKW frequency, necessitating a ±500-PPM crystal.
20. The PECL switching threshold is the midpoint between the PECL− VOH, and VOL specification (approximately VCC − 1.35V). The TTL switching threshold is 1.5V.
21. Static alignment is a measure of the alignment of the Receiver sampling point to the center of a bit. Static alignment is measured by sliding one bit edge in
3,000 nominal transitions until a byte error occurs.
22. Error Free Window is a measure of the time window between bit centers where a transition may occur without causing a bit sampling error. EFW is measured
over the operating range, input jitter < 50% Dj.
10
CY7B923
CY7B933
Switching Waveforms for the CY7B923 HOTLink Transmitter
tCKW
tCPWH
tCPWL
CKW
tSENP
tHENP
tSD
ENA
NOTES 10,11
D0–D7,
SC/D,
SVS,
BISTEN
VALID DATA
tSD
tHD
DISABLED
tPDF
RP
ENABLED
tPDR
B923–11
tPPWH
tCKW
CKW
tCPWH
tCPWL
tSD
tHD
ENN
D0–D7,
SC/D,
SVS,
BISTEN
VALID DATA
B923–12
tSD
11
tHD
CY7B923
CY7B933
Switching Waveforms for the CY7B933 HOTLink Receiver
tCKR
tCPRH
tCPRL
CKR
tPRH
tRH
tPRF
RDY
tH
tA
tROH
Q0 − Q7,
SC/D,RVS,
B923–13
tCKX
tCPXL
tCPXH
REFCLK
B923–14
SI
VBB
tDS
SO
NOTE 20
1.5V
B923–15
Static Alignment
Error-F ree Window
tB/2− tSA
tB/2− tSA
tEFW
INA±
INB±
INA± ,
INB±
tB
SAMPLE WINDOW
B923–16
12
BIT CENTER
BIT CENTER
B923–17
CY7B923
CY7B933
DATA LATCHED IN
TRANSMITTER LATENCY = 21 tB − 10ns
CKW
ENA
D0−7,
SC/D,
SVS
DATA
RP
OUTX±
DATA
K28.5
K28.5
DATA SENT
B923–18
Figure 2. CY7B923 Transmitter Data Pipeline
ceiver on the INx± inputs. The receiver PLL locks onto the
serial bit stream and generates an internal bit rate clock. The
bit stream is deserialized, decoded and then presented at the
parallel output pins. A byte rate clock (bit clock ÷ 10) synchronous with the parallel data is presented at the CKR pin. The
RDY pin will be asserted to LOW to indicate that data or control
characters are present on the outputs. RDY will not be asserted LOW in a field of K28.5s except for any single K28.5 or the
last one in a continuous series of K28.5’s. The latency through
the receiver is approximately 24tB + 10 ns over the operating
range. A more complete description of the receiver is in the
section CY7B933 HOTLink Receiver Operating Mode Description
HOTLink CY7B923 Transmitter and CY7B933
Receiver Operation
The CY7B923 Transmitter operating with the CY7B933 Receiver form a general purpose data communications subsystem capable of transporting user data at up to 33Mbytes
per second (40 Mbytes per second for -400 devices) over several types of serial interface media. Figure 2 illustrates the flow
of data through the HOTLink CY7B923 transmitter pipeline. Data is
latched into the transmitter on the rising edge of CKW when enabled
by ENA or ENN. RP is asserted LOW with a 60% LOW/40% HIGH
duty cycle when ENA is LOW. RP may be used as a read strobe for
accessing data stored in a FIFO. The parallel data flows through the
encoder and is then shifted out of the OUTx± PECL drivers. The
bit-rate clock is generated internally from a multiply-by-ten PLL clock
generator. The latency through the transmitter is approximately 21tB
− 10 ns over the operating range. A more complete description is
found in the section CY7B923 HOTLink Transmitter Operating Mode
Description.
The HOTLink Receiver has a built-in byte framer that synchronizes the Receiver pipeline with incoming SYNC (K28.5) characters. Figure 4 illustrates the HOTLink CY7B933 Receiver framing
operation. The Framer is enabled when the RF pin is asserted HIGH.
RF is latched into the receiver on the falling edge of CKR. The framer
looks for K28.5 characters embedded in the serial data stream. When
a K28.5 is found, the framer sets the parallel byte boundary for subsequent data to the K28.5 boundary. While the framer is enabled, the
RDY pin indicates the status of the framing operation.
Figure 3 illustrates the data flow through the HOTLink
CY7B933 receiver pipeline. Serial data is sampled by the reSERIAL DATA IN
RECEIVER LATENCY= 24 t B + 10 ns
INX±
DATA
CKR
Q0−7,
SC/D,
RVS
DATA
RDY
K28.5
K28.5
DATA
RDY IS HIGH IN FIELD OF K28.5S
RDY IS LOW FOR DATA
RDY IS LOW FOR LAST K28.5
PARALLEL
DATA OUT
B923–19
Figure 3. CY7B933 Receiver Data Pipeline in Encoded Mode
13
CY7B923
CY7B933
RF LATCHED ON
FALLING EDGE OF CKR
CKR STRETCHES AS
DATA BOUNDARY CHANGES
CKR
RF
Q0−7,
SC/D,
RVS
RDY
DATA
DATA
DATA
DATA
DATA
K28.5
DATA
DATA
RDY IS HIGH WHILE WAITING FOR K28.5
RDY IS LOW
FOR K28.5
RDY RESUMES
NORMAL
OPERATION
B923–20
Figure 4. CY7B933 Framing Operation in Encoded Mode
receive eight (8) bit data and control information without first
converting it to transmission characters. The Bypass mode is
used for systems in which the encoding and decoding is performed in an external protocol controller.
When the RF pin is asserted HIGH, RDY leaves it normal mode
of operation and is asserted HIGH while the framer searches the data
stream for a K28.5 character. After the framer has synchronized to a
K28.5 character, the Receiver will assert the RDY pin LOW when the
K28.5 character is present at the parallel output. The RDY pin will
then resume its normal operation as dictated by the MODE and BISTEN pins.
In either mode, data is loaded into the Input register of the
Transmitter on the rising edge of CKW. The input timing and
functional response of the Transmitter input can be made to
match the timing and functionality of either an asynchronous
FIFO or a clocked FIFO by an appropriate connection of input
signals (See Figure 5). Proper operation of the FIFO interface depends upon various FIFO-specific access and response specifications.
The normal operation of the RDY pin in encoded mode is to signal
when parallel data is present at the output pins by pulsing LOW with
a 60% LOW/40% HIGH duty cycle. RDY does not pulse LOW in a
field of K28.5 characters; however, RDY does pulse LOW for the last
K28.5 character in the field or for any single K28.5. In unencoded
mode, the normal operation of the RDY pin is to signal when any
K28.5 is at the parallel output pins.
Encoded Mode Operation
In Encoded mode the input data is interpreted as eight bits of
data (D0 − D7), a context control bit (SC/D), and a system diagnostic
input bit (SVS). If the context of the data is to be normal message
data, the SC/D input should be LOW, and the data should be encoded using the valid data character set described in the Valid Data Characters section of this datasheet. If the context of the data is to be
control or protocol information, the SC/D input will be HIGH, and the
data will be encoded using the valid special character set described
in the Valid Special Character Codes and Sequences section. Special characters include all protocol characters necessary to encode
packets for Fibre Channel, ESCON, proprietary systems, and diagnostic purposes.
The Transmitter and Receiver parallel interface timing and
functionality can be made to match the timing and functionality
of either an asynchronous FIFO or a clocked FIFO by appropriately connecting signals (See Figure 5). Proper operation of
the FIFO interface depends upon various FIFO-specific access and
response specifications.
The HOTLink Transmitter and Receiver serial interface provides a seamless interface to various types of media. A minimal number of external components are needed to properly
terminate transmission lines and provide PECL loads. For
proper power supply decoupling, a single 0.01 µF for each device is all that is required to bypass the VCC and GND pins. Figure
6 illustrates a HOTLink Transmitter and Receiver interface to fiber
optic and copper media. More information on interfacing HOTLink to
various media can be found in the HOTLink Design Considerations
application note.
The diagnostic characters and sequences available as Special
Characters include those for Fibre Channel link testing, as well
as codes to be used for testing system response to link errors
and timing. A Violation symbol can be explicitly sent as part
of a user data packet (i.e., send C0.7; D 7−0 = 111 00000 and
SC/D = 1), or it can be sent in response to an external system using
the SVS input. This will allow system diagnostic logic to evaluate the
errors in an unambiguous manner, and will not require any modification to the transmission interface to force transmission errors for testing purposes.
CY7B923 HOTLink Transmitter Operating Mode
Description
In normal operation, the Transmitter can operate in either of
two modes. The Encoded mode allows a user to send and
14
FROM CONTROLLER
CY7B923
CY7B933
ASYNCHRONOUS FIFO
CLOCKED FIFO
7C42X/3X/6X/7X
7C44X/5X
R
Q0 − 8
ENR
CKR
Q0 − 8
9
9
ENA
CKW
RP
D0 − 7,SC/D
ENN
CKW
D0 − 7,SC/D
7B923
7B923
HOTLINK TRANSMITTER
HOTLINK TRANSMITTER
HOTLINK RECEIVER
HOTLINK RECEIVER
7B933
7B933
CKR
RDY
Q0 − 7,SC/D
CKR
RDY
Q0 − 7,SC/D
9
W
9
D0 − 8
CKW
ENW
7C42X/3X/6X/7X
7C44X/5X
ASYNCHRONOUS FIFO
CLOCKED FIFO
D0 − 8
B923–21
Figure 5. Seamless FIFO Interface
Bypass Mode Operation
to maintain proper link synchronization (in Bypass mode the proper
sense of running disparity cannot be guaranteed for the first pad character, but is correct for all pad characters that follow). This automatic
insertion of pad characters can be inhibited by insuring that the Transmitter is always enabled (i.e., ENA or ENN is hard-wired LOW).
In Bypass mode the input data is interpreted as ten (10) bits
(Db-h), SC/D (Da), and SVS (Dj) of pre-encoded transmission data to
be serialized and sent over the link. This data can use any encoding
method suitable to the designer. The only restrictions upon the data
encoding method is that it contain suitable transition density for the
Receiver PLL data synchronizer (one per 10 bit byte), and that it be
compatible with the transmission media.
PECL Output Functional and Connection Options
The three pairs of PECL outputs all contain the same information and are intended for use in systems with multiple connections. Each output pair may be connected to a different serial
media, each of which may be a different length, link type, or
interface technology. For systems that do not require all three
output pairs, the unused pairs should be wired to VCC to minimize the power dissipated by the output circuit, and to minimize unwanted noise generation. An internal voltage comparator detects
when an output differential pair is wired to VCC, causing the current
source for that pair to be disabled. This results in a power savings of
around 5 mA for each unused pair.
Data loaded into the Input register on the rising edge of CKW
will be loaded into the Shifter on the subsequent rising edges
of CKW. It will then be shifted to the outputs one bit at a time
using the internal clock generated by the clock generator. The
first bit of the transmission character (Da) will appear at the output (OUTA±, OUTB±, and OUTC±) after the next CKW edge.
While in either the Encoded mode or Bypass mode, if a CKW
edge arrives when the inputs are not enabled (ENA and ENN
both HIGH), the Encoder will insert a pad character K28.5 (e.g., C5.0)
15
CY7B923
CY7B933
rial data output is controlled by an internal Phase-Locked Loop
that multiplies the frequency of CKW by ten (10) to maintain
the proper bit clock frequency. The jitter characteristics (including both PLL and logic components) are shown below:
In systems that require the outputs to be shut off during some
periods when link transmission is prohibited (e.g., for laser
safety functions), the FOTO input can be asserted. While it is
possible to insure that the output state of the PECL drivers is
LOW (i.e., light is off) by sending all 0’s in Bypass mode, it is
often inconvenient to insert this level of control into the data
transmission channel, and it is impossible in Encoded mode.
FOTO is provided to simplify and augment this control function
(typically found in laser-based transmission systems). FOTO
will force OUTA+ and OUTB+ to go LOW, OUTA− and OUTB−
to go HIGH, while allowing OUTC± to continue to function normally (OUTC is typically used as a diagnostic feedback and cannot be
disabled). This separation of function allows various system configurations without undue load on the control function or data channel
logic.
Deterministic Jitter (Dj) < 35 ps (peak-peak). Typically measured while sending a continuous K28.5 (C5.0).
Random Jitter (Rj) < 175 ps (peak-peak). Typically measured
while sending a continuous K28.7 (C7.0).
Transmitter Test Mode Description
The CY7B923 Transmitter offers two types of test mode operation, BIST mode and Test mode. In a normal system application, the Built-In Self-Test (BIST) mode can be used to check
the functionality of the Transmitter, the Receiver, and the link
connecting them. This mode is available with minimal impact
on user system logic, and can be used as part of the normal
system diagnostics. Typical connections and timing are shown
in Figure 7.
Transmitter Serial Data Characteristics
The CY7B923 HOTLink Transmitter serial output conforms to
the requirements of the Fibre Channel specification. The se-
Config
Control
&
Status
Data
4
25
5
24
23
8
19
18
17
16
15
14
13
12
11
10
21
MODE
.01UF
4 9 22
VCC
FOTO
BISTEN
OUTA+
ENN
OUTA–
ENA CY7B923
RP Transmitter
OUTB+
SC/D (Da)
OUTB–
D0 (Db)
D1 (Dc)
D2 (Dd)
OUTC+
D3 (De)
OUTC–
D4 (Di)
D5 (Df)
D6 (Dg)
D7 (Dh)
SVS (Dj)
CKW
GND
6 20
Tx PECL Load
82
130
82
130
.01UF
VCC
Fiber
TX+ TX
TX–
A
27
26
B
28 Unused Ouput Left
1 Open to Minimize
Power Dissipation
GND
.01UF
Tx PECL Load
270
3
2
Coax or
Twisted Pair
A
270
B
270
.01UF
Control
&
Status
Data
9 21 24
26
VCC
25 MODE
REFCLK
4
23
3
5
7
19
18
17
16
15
14
13
12
11
10
22
Transmission
Line
Termination
C
1500
RL/2
Coax or
Twisted Pair
RL/2
D
BISTEN
SO
CY7B933
A/B
Receiver
28
RF
IB+ 27
RDY
IB–
SC/D (Qa)
D0 (Qb)
D1 (Qc)
D2 (Qd)
D3 (Qe)
IA+
D4 (Qi)
IA–
D5 (Qf)
D6 (Qg)
D7 (Qh)
RVS(Qj)
CKR GND
6 8 20
270
.01UF
649
Config
Fiber Optic
Tx
Optional
Signal Det.
E
E
270
2
1
82
130
82
130
C
D
.01UF
VCC
Fiber
SIG
RX+ RX
RX–
Fiber Optic
Rx
GND
.01UF
Fiber Optic
PECL Load
B923–22
Figure 6. HOTLink Connection Diagram
16
CY7B923
CY7B933
CY7B923
DON'T CARE
DON'T CARE
BIST
LOOP
WITHIN SPEC.
FOTO
MODE
CKW
RP
DON'T CARE
SC/D
OUTA
D0 − 7
OUTB
SVS
OUTC
DON'T CARE
8
LOW
ENA
Tx
START
Tx
STOP
HIGH
ENN
BISTEN
CY7B933
WITHIN SPEC.
DON'T CARE
LOW
REFCLK
MODE
RF
SO
CKR
DON'T CARE
SC/D
8
ERROR
INA
Q0 − 7
INB
RVS
TEST
START
BIST
LOOP
Rx
BEGIN
TEST
A/B
LOW
RDY
BISTEN
TEST
END
B923–23
Figure 7. Built In Self-Test Illustration
3. Allow the Transmitter to run through several BIST loops or
until the Receiver test is complete. RP will pulse LOW once
per BIST loop, and can be used by an external counter to
monitor the number of test pattern loops.
BIST Mode
BIST mode functions as follows:
1. Set BISTEN LOW to begin test pattern generation. Transmitter begins sending bit rate ...1010...
4. When testing is completed, set BISTEN HIGH and ENA and
ENN HIGH and resume normal function.
2. Set either ENA or ENN LOW to begin pattern sequence
generation (use of the Enable pin not being used for normal
FIFO or system interface can minimize logic delays between the controller and transmitter).
Note: It may be advisable to send violation characters to test
the RVS output in the Receiver. This can be done by explicitly
sending a violation with the SVS input, or allowing the trans-
17
CY7B923
CY7B933
mitter BIST loop to run while the Receiver runs in normal
mode. The BIST loop includes deliberate violation symbols
and will adequately test the RVS function.
CY7B933 HOTLink Receiver Operating Mode
Description
BIST mode is intended to check the entire function of the
Transmitter (except the Transmitter input pins and the bypass
function in the Encoder), the serial link, and the Receiver. It
augments normal factory ATE testing and provides the designer with a rigorous test mechanism to check the link transmission system without requiring any significant system overhead.
In normal user operation, the Receiver can operate in either of
two modes. The Encoded mode allows a user system to send
and receive 8-bit data and control information without first converting it to transmission characters. The Bypass mode is
used for systems in which the encoding and decoding is performed by an external protocol controller.
In either mode, serial data is received at one of the differential
line receiver inputs and routed to the Shifter and the Clock
Synchronization. The PLL in the Clock Synchronizer aligns
the internally generated bit rate clock with the incoming data
stream and clocks the data into the shifter. At the end of a byte
time (ten bit times), the data accumulated in the shifter is transferred to the Decode register.
While in Bypass mode, the BIST logic will function in the same
way as in the Encoded mode. MODE = HIGH and BISTEN =
LOW causes the Transmitter to switch to Encoded mode and begin
sending the BIST pattern, as if MODE = LOW. When BISTEN returns to HIGH, the Transmitter resumes normal Bypass operation. In
Test mode the BIST function works as in the Normal mode. For more
information on BIST, consult the “HOTLink Built-In Self-Test” Application Note.
To properly align the incoming bit stream to the intended byte
boundaries, the bit counter in the Clock Synchronizer must be
initialized. The Framer logic block checks the incoming bit
stream for the unique pattern that defines the byte boundaries.
This combinatorial logic filter looks for the X3.230 symbol defined as “Special Character Comma” (K28.5). Once K28.5 is
found, the free running bit counter in the Clock Synchronizer
block is synchronously reset to its initial state, thus “framing”
the data to the correct byte boundaries.
Test Mode
The MODE input pin selects between three transmitter functional modes. When wired to VCC, the D(a−j) inputs bypass the
Encoder and load directly from the Input register into the Shifter.
When wired to GND, the inputs D0−7, SVS, and SC/D are encoded
using the Fibre Channel 8B/10B codes and sequences (shown at the
end of this datasheet). Since the Transmitter is usually hard wired to
Encoded or Bypass mode and not switched between them, a third
function is provided for the MODE pin. Test mode is selected by
floating the MODE pin (internal resistors hold the MODE pin at
VCC/2). Test mode is used for factory or incoming device test.
Since noise-induced errors can cause the incoming data to be
corrupted, and since many combinations of error and legal
data can create an alias K28.5, an option is included to disable
resynchronization of the bit counter. The Framer will be inhibited when the RF input is held LOW. When RF rises, RDY will
be inhibited until a K28.5 has been detected, and RDY will
resume its normal function. Data will continue to flow through
the Receiver while RDY is inhibited.
Test mode causes the Transmitter to function in its Encoded
mode, but with OutA+/OutB+ (used as a differential test clock
input) as the bit rate clock input instead of the internal
PLL-generated bit clock. In this mode, inputs are clocked by
CKW and transfers between the Input register and Shifter are
timed by the internal counters. The bit-clock and CKW must
maintain a fixed phase and divide-by-ten ratio. The phase and
pulse width of RP are controlled by phases of the bit counter (PLL
feedback counter) as in Normal mode. Input and output patterns can
be synchronized with internal logic by observing the state of RP or the
device can be initialized to match an ATE test pattern using the following technique:
Encoded Mode Operation
In Encoded mode the serial input data is decoded into eight
bits of data (Q0 − Q7), a context control bit (SC/D), and a system
diagnostic output bit (RVS). If the pattern in the Decode register is
found in the Valid Data Characters table, the context of the data is
decoded as normal message data and the SC/D output will be
LOW. If the incoming bit pattern is found in the Valid Special Character Codes and Sequences table, it is interpreted as “control” or
“protocol information,” and the SC/D output will be HIGH. Special
characters include all protocol characters defined for use in packets
for Fibre Channel, ESCON, and other proprietary and diagnostic
purposes.
1. With the MODE pin either HIGH or LOW, stop CKW and
bit-clock.
2. Force the MODE pin to MID (open or VCC/2) while the
clocks are stopped.
The Violation symbol that can be explicitly sent as part of a
user data packet (i.e., Transmitter sending C0.7; D7−0 = 111
00000 and SC/D = 1; or SVS = 1) will be decoded and indicated in
exactly the same way as a noise-induced error in the transmission
link. This function will allow system diagnostics to evaluate the error
in an unambiguous manner, and will not require any modification to
the receiver data interface for error-testing purposes.
3. Start the bit-clock and let it run for at least 2 cycles.
4. Start the CKW clock at the bit-clock/10 rate.
Test mode is intended to allow logical, DC, and AC testing of
the Transmitter without requiring that the tester check output
data patterns at the bit rate, or accommodate the PLL lock,
tracking, and frequency range characteristics that are required
when the HOTLink part operates in its normal mode. To use
OutA+/OutB+ as the test clock input, the FOTO input is held
HIGH while in Test mode. This forces the two outputs to go to
an “PECL LOW,” which can be ignored while the test system
creates a differential input signal at some higher voltage.
Bypass Mode Operation
In Bypass mode the serial input data is not decoded, and is
transferred directly from the Decode register to the Output register’s 10 bits (Q(a−j). It is assumed that the data has been pre-encoded prior to transmission, and will be decoded in subsequent logic external to HOTLink. This data can use any encoding method
suitable to the designer. The only restrictions upon the data encoding method is that it contain suitable transition density for the Re-
18
CY7B923
CY7B933
RVS SC/D QoutsName
ceiver PLL data synchronizer (one per 10 bit byte) and that it be
compatible with the transmission media.
1. Good Data code received
with good Running Disparity
(RD)0000−FFD0.0−31.7
The framer function in Bypass mode is identical to Encoded
mode, so a K28.5 pattern can still be used to re-frame the
serial bit stream.
2. Good Special Character
code received with good RD
0
1
00−0B C0.0−11.0
The 10 outputs (Q0−7, SC/D, and RVS) all transition simultaneously, and are aligned with RDY and CKR with timing allowances to
interface directly with either an asynchronous FIFO or a clocked
FIFO. Typical FIFO connections are shown in Figure 5.
3. K28.7 immediately following
K28.1 (ESCON Connect_SOF)0
1
27
C7.1
4. K28.7 immediately following
K28.5 (ESCON Passive_SOF)0
1
47
C7.2
Data outputs can be clocked into the system using either the
rising or falling edge of CKR, or the rising or falling edge of
RDY. If CKR is used, RDY can be used as an enable for the receiving logic. A LOW pulse on RDY shows that new data has been
received and is ready to be delivered. The signal on RDY is a
60%−LOW duty cycle byte-rate pulse train suitable for the write
pulse in asynchronous FIFOs such as the CY7C42X, or the enable
write input on Clocked FIFOs such as the CY7C44X. HIGH on
RDY shows that the received data appearing at the outputs is the
null character (normally inserted by the transmitter as a pad between data inputs) and should be ignored.
5. Unassigned code received
1
1
E0
C0.7
6. −K28.5+ received when
RD was +
1
1
E1
C1.7
7. +K28.5− received when
RD was −
1
1
E2
C2.7
8. Good code received
with wrong RD
1
1
E4
C4.7
Parallel Output Function
Receiver Serial Data Requirements
The CY7B933 HOTLink Receiver serial input capability conforms to the requirements of the Fibre Channel specification.
The serial data input is tracked by an internal Phase-Locked
Loop that is used to recover the clock phase and to extract the
data from the serial bit stream. Jitter tolerance characteristics
(including both PLL and logic component requirements) are
shown below:
When the Transmitter is disabled it will continuously send pad
characters (K28.5). To assure that the receive FIFO will not
be overfilled with these dummy bytes, the RDY pulse output is
inhibited during fill strings. Data at the Q0−7 outputs will reflect the
correct received data, but will not appear to change, since a string
of K28.5s all are decoded as Q7−0 =000 00101 and SC/D = 1
(C5.0). When new data appears (not K28.5), the RDY output will
resume normal function. The “last” K28.5 will be accompanied by
a normal RDY pulse.
Deterministic Jitter tolerance (Dj) >40% of tB. Typically measured while receiving data carried by a bandwidth-limited channel (e.g., a coaxial transmission line) while maintaining a Bit Error Rate (BER) <10−12.
Fill characters are defined as any K28.5 followed by another
K28.5. All fill characters will not cause RDY to pulse. Any K28.5
followed by any other character (including violation or illegal characters) will be interpreted as usable data and will cause RDY to pulse.
Random Jitter tolerance (Rj) > 90% of tB. Typically measured
while receiving data carried by a random-noise-limited channel
(e.g., a fiber-optic transmission system with low light levels) while
maintaining a Bit Error Rate (BER) <10−12.
As noted above, RDY can also be used as an indication of correct
framing of received data. While the Receiver is awaiting receipt of
a K28.5 with RF HIGH, the RDY outputs will be inhibited. When
RDY resumes, the received data will be properly framed and will be
decoded correctly. In Bypass mode with RF HIGH, RDY will pulse
once for each K28.5 received. For more information on the RDY
pin, consult the “HOTLink CY7B933 RDY Pin Description” application note.
Total Jitter tolerance >90% of tB. Total of Dj + Rj.
PLL-Acquisition time <500-bit times from worst-case phase
or frequency change in the serial input data stream, to receiving data within BER objective of 10 −12. Stable power
supplies within specifications, stable REFCLK input frequency
and normal data framing protocols are assumed. Note: Acquisition time is measured from worst-case phase or frequency
change to zero phase and frequency error. As a result of the
receiver’s wide jitter tolerance, valid data will appear at the receiver’s outputs a few byte times after a worst-case phase
change.
Code rule violations and reception errors will be indicated as
follows:
19
CY7B923
CY7B933
Receiver Test Mode Description
logic and test pattern inputs can be synchronized by sending
a SYNC pattern and allowing the Framer to align the logic to
the bit stream. The flow is as follows:
The CY7B933 Receiver offers two types of test mode operation, BIST mode and Test mode. In a normal system application, the Built-In Self-Test (BIST) mode can be used to check
the functionality of the Transmitter, the Receiver and the link
connecting them. This mode is available with minimal impact
on user system logic, and can be used as part of the normal
system diagnostics. Typical connections and timing are shown
in Figure 7.
1. Assert Test mode for several test clock cycles to establish
normal counter sequence.
2. Assert RF to enable reframing.
3. Input a repeating sequence of bits representing K28.5
(Sync).
4. RDY falling shows the byte boundary established by the
K28.5 input pattern.
BIST Mode
5. Proceed with pattern, voltage and timing tests as is convenient for the test program and tester to be used.
BIST Mode function is as follows:
1. Set BISTEN LOW to enable self-test generation and await
RDY LOW indicating that the initialization code has been
received.
(While in Test mode and in BIST mode with RF HIGH, the Q0-7,
RVS, and SC/D outputs reflect various internal logic states and not
the received data.)
2. Monitor RVS and check for any byte time with the pin HIGH
to detect pattern mismatches. RDY will pulse HIGH once
per BIST loop, and can be used by an external counter to
monitor test pattern progress. Q0−7 and SC/D will show the
expected pattern and may be useful for debug purposes.
Test mode is intended to allow logical, DC, and AC testing of
the Receiver without requiring that the tester generate input
data at the bit rate or accommodate the PLL lock, tracking and
frequency range characteristics that are required when the
part operates in its normal mode.
3. When testing is completed, set BISTEN HIGH and resume
normal function.
X3.230 Codes and Notation Conventions
Note: A specific test of the RVS output may be required to
assure an adequate test. To perform this test, it is only necessary to have the Transmitter send violation (SVS = HIGH) for
a few bytes before beginning the BIST test sequence. Alternatively, the Receiver could enter BIST mode after the Transmitter has begun sending BIST loop data, or be removed before the Transmitter finishes sending BIST loops, each of
which contain several deliberate violations and should cause
RVS to pulse HIGH.
Information to be transmitted over a serial link is encoded eight
bits at a time into a 10-bit Transmission Character and then
sent serially, bit by bit. Information received over a serial link
is collected ten bits at a time, and those Transmission Characters that are used for data (Data Characters) are decoded into
the correct eight-bit codes. The 10-bit Transmission Code
supports all 256 8-bit combinations. Some of the remaining
Transmission Characters (Special Characters) are used for
functions other than data transmission.
BIST mode is intended to check the entire function of the
Transmitter, serial link, and Receiver. It augments normal factory ATE testing and provides the user system with a rigorous
test mechanism to check the link transmission system, without
requiring any significant system overhead.
When in Bypass mode, the BIST logic will function in the same
way as in the Encoded mode. MODE = HIGH and BISTEN =
LOW causes the Receiver to switch to Encoded mode and begin
checking the decoded received data of the BIST pattern, as if
MODE = LOW. When BISTEN returns to HIGH, the Receiver resumes normal Bypass operation. In Test mode the BIST function
works as in the normal mode.
The primary rationale for use of a Transmission Code is to
improve the transmission characteristics of a serial link. The
encoding defined by the Transmission Code ensures that sufficient transitions are present in the serial bit stream to make
clock recovery possible at the Receiver. Such encoding also
greatly increases the likelihood of detecting any single or multiple bit errors that may occur during transmission and reception of information. In addition, some Special Characters of
the Transmission Code selected by Fibre Channel Standard
consist of a distinct and easily recognizable bit pattern (the
Special Character Comma) that assists a Receiver in achieving word alignment on the incoming bit stream.
Test Mode
Notation Conventions
The MODE input pin selects between three receiver functional
modes. When wired to VCC, the Shifter contents bypass the
Decoder and go directly from the Decoder latch to the Qa−j inputs
of the Output latch. When wired to GND, the outputs are decoded
using the 8B/10B codes shown at the end of this datasheet and
become Q0−7, RVS, and SC/D. The third function is Test mode,
used for factory or incoming device test. This mode can be selected
by leaving the MODE pin open (internal circuitry forces the open pin
to VCC/2).
The documentation for the 8B/10B Transmission Code uses
letter notation for the bits in an 8-bit byte. Fibre Channel Standard notation uses a bit notation of A, B, C, D, E, F, G, H for
the 8-bit byte for the raw 8-bit data, and the letters a, b, c, d,
e, i, f, g, h, j for encoded 10-bit data. There is a correspondence between bit A and bit a, B and b, C and c, D and d, E
and e, F and f, G and g, and H and h. Bits i and j are derived,
respectively, from (A,B,C,D,E) and (F,G,H).
The bit labeled A in the description of the 8B/10B Transmission
Code corresponds to bit 0 in the numbering scheme of the
FC-2 specification, B corresponds to bit 1, as shown below.
Test mode causes the Receiver to function in its Encoded
mode, but with INB (INB+) as the bit rate Test clock instead of
the Internal PLL generated bit clock. In this mode, transfers
between the Shifter, Decoder register and Output register are
controlled by their normal logic, but with an external bit rate
clock instead of the PLL (the recovered bit clock). Internal
FC-2 bit designation—
7 6 5
HOTLink D/Q designation— 7 6 5
8B/10B bit designation—
H G F
20
4 3 2 1 0
4 3 2 1 0
E D C B A
CY7B923
CY7B933
Transmission Order
To clarify this correspondence, the following example shows
the conversion from an FC-2 Valid Data Byte to a Transmission
Character (using 8B/10B Transmission Code notation)
Within the definition of the 8B/10B Transmission Code, the bit
positions of the Transmission Characters are labeled a, b, c,
d, e, i, f, g, h, j. Bit “a” shall be transmitted first followed by bits
b, c, d, e, i, f, g, h, and j in that order. (Note that bit i shall be
transmitted between bit e and bit f, rather than in alphabetical
order.)
FC-2 45
Bits: 7654 3210
0100 0101
Converted to 8B/10B notation (note carefully that the order of
bits is reversed):
Data Byte Name
Valid and Invalid Transmission Characters
D5.2
Bits:ABCDEFGH
10100 010
The following tables define the valid Data Characters and valid
Special Characters (K characters), respectively. The tables
are used for both generating valid Transmission Characters
(encoding) and checking the validity of received Transmission
Characters (decoding). In the tables, each Valid-Data-byte or
Special-Character-code entry has two columns that represent
two (not necessarily different) Transmission Characters. The
two columns correspond to the current value of the running
disparity (“Current RD−” or “Current RD+”). Running disparity
is a binary parameter with either the value negative (−) or the
value positive (+).
Translated to a transmission Character in the 8B/10B Transmission Code:
Bits: abcdeifghj
1010010101
Each valid Transmission Character of the 8B/10B Transmission Code has been given a name using the following convention: cxx.y, where c is used to show whether the Transmission
Character is a Data Character (c is set to D, and the SC/D pin
is LOW) or a Special Character (c is set to K, and the SC/D pin is
HIGH). When c is set to D, xx is the decimal value of the binary
number composed of the bits E, D, C, B, and A in that order, and
the y is the decimal value of the binary number composed of the bits
H, G, and F in that order. When c is set to K, xx and y are derived
by comparing the encoded bit patterns of the Special Character to
those patterns derived from encoded Valid Data bytes and selecting
the names of the patterns most similar to the encoded bit patterns
of the Special Character.
After powering on, the Transmitter may assume either a positive or negative value for its initial running disparity. Upon
transmission of any Transmission Character, the transmitter
will select the proper version of the Transmission Character
based on the current running disparity value, and the Transmitter shall calculate a new value for its running disparity
based on the contents of the transmitted character. Special
Character codes C1.7 and C2.7 can be used to force the transmission of a specific Special Character with a specific running
disparity as required for some special sequences in X3.230.
Under the above conventions, the Transmission Character
used for the examples above, is referred to by the name D5.2.
The Special Character K29.7 is so named because the first six
bits (abcdei) of this character make up a bit pattern similar to
that resulting from the encoding of the unencoded 11101 pattern (29), and because the second four bits (fghj) make up a
bit pattern similar to that resulting from the encoding of the
unencoded 111 pattern (7).
After powering on, the Receiver may assume either a positive
or negative value for its initial running disparity. Upon reception of any Transmission Character, the Receiver shall decide
whether the Transmission Character is valid or invalid according to the following rules and tables and shall calculate a new
value for its Running Disparity based on the contents of the
received character.
The following rules for running disparity shall be used to calculate the new running-disparity value for Transmission Characters that have been transmitted (Transmitter’s running disparity) and that have been received (Receiver’s running
disparity).
Note: This definition of the 10-bit Transmission Code is based
on (and is in basic agreement with) the following references,
which describe the same 10-bit transmission code.
A.X. Widmer and P.A. Franaszek. “A DC-Balanced, Partitioned-Block, 8B/10B Transmission Code” IBM Journal of Research and Development, 27, No. 5: 440−451 (September, 1983).
Running disparity for a Transmission Character shall be calculated from sub-blocks, where the first six bits (abcdei) form one
sub-block and the second four bits (fghj) form the other
sub-block. Running disparity at the beginning of the 6-bit
sub-block is the running disparity at the end of the previous
Transmission Character. Running disparity at the beginning of
the 4-bit sub-block is the running disparity at the end of the
6-bit sub-block. Running disparity at the end of the Transmission Character is the running disparity at the end of the 4-bit
sub-block.
U.S. Patent 4,488,739. Peter A. Franaszek and Albert X. Widmer. “Byte-Oriented DC Balanced (0.4) 8B/10B Partitioned
Block Transmission Code” (December 4, 1984).
Fibre Channel Physical and Signaling Interface (dpANS
X3.230−199X ANSI FC−PH Standard).
IBM Enterprise Systems Architecture/390 ESCON I/O Interface (document number SA22−7202).
8B/10B Transmission Code
Running disparity for the sub-blocks shall be calculated as follows:
The following information describes how the tables shall be
used for both generating valid Transmission Characters (encoding) and checking the validity of received Transmission
Characters (decoding). It also specifies the ordering rules to
be followed when transmitting the bits within a character and
the characters within the higher-level constructs specified by
the standard.
1. Running disparity at the end of any sub-block is positive if
the sub-block contains more ones than zeros. It is also
positive at the end of the 6-bit sub-block if the 6-bit
sub-block is 000111, and it is positive at the end of the 4-bit
sub-block if the 4-bit sub-block is 0011.
2. Running disparity at the end of any sub-block is negative if
the sub-block contains more zeros than ones. It is also
21
CY7B923
CY7B933
ceiver’s current running disparity for the next received Transmission Character.
negative at the end of the 6-bit sub-block if the 6-bit
sub-block is 111000, and it is negative at the end of the 4-bit
sub-block if the 4-bit sub-block is 1100.
Table 1. Valid Transmission Characters
3. Otherwise, running disparity at the end of the sub-block is
the same as at the beginning of the sub-block.
Data
DIN or QOUT
Use of the Tables for Generating Transmission Characters
The appropriate entry in the table shall be found for the Valid
Data byte or the Special Character byte for which a Transmission Character is to be generated (encoded). The current value of the Transmitter’s running disparity shall be used to select
the Transmission Character from its corresponding column.
For each Transmission Character transmitted, a new value of
the running disparity shall be calculated. This new value shall
be used as the Transmitter’s current running disparity for the
next Valid Data byte or Special Character byte to be encoded
and transmitted. Table 1 shows naming notations and examples
of valid transmission characters.
Use of the Tables for Checking the Validity of Received
Transmission Characters
The column corresponding to the current value of the Receiver’s running disparity shall be searched for the received Transmission Character. If the received Transmission Character is
found in the proper column, then the Transmission Character
is valid and the associated Data byte or Special Character
code is determined (decoded). If the received Transmission
Character is not found in that column, then the Transmission
Character is invalid. This is called a code violation. Independent of the Transmission Character’s validity, the received
Transmission Character shall be used to calculate a new value
of running disparity. The new value shall be used as the Re-
Byte Name
765
43210
Hex Value
D0.0
000
00000
00
D1.0
000
00001
01
D2.0
000
00010
02
.
.
.
.
.
.
.
.
D5.2
010
00010
1
45
.
.
.
.
.
.
.
.
D30.7
111
11110
FE
D31.7
111
11111
FF
Detection of a code violation does not necessarily show that
the Transmission Character in which the code violation was
detected is in error. Code violations may result from a prior
error that altered the running disparity of the bit stream which
did not result in a detectable error at the Transmission Character in which the error occurred. Table 2 shows an example of
this behavior.
Table 2. Code Violations Resulting from Prior Errors
RD
Character
RD
Character
RD
Character
RD
Transmitted data character
−
D21.1
−
D10.2
−
D23.5
+
Transmitted bit stream
−
101010 1001
−
010101 0101
−
111010 1010
+
Bit stream after error
−
101010 1011
+
010101 0101
+
111010 1010
+
Decoded data character
−
D21.0
+
D10.2
+
Code Violation
+
22
CY7B923
CY7B933
Valid Data Characters (SC/D = LOW)
Data
Byte
Name
Bits
Current RD−
Current RD+
HGF
EDCBA
abcdei
fghj
abcdei
fghj
D0.0
000
00000
100111
0100
011000
1011
D1.0
000
00001
011101
0100
100010
1011
D2.0
000
00010
101101
0100
010010
1011
D3.0
000
00011
110001
1011
110001
0100
D4.0
000
00100
110101
0100
001010
1011
D5.0
000
00101
101001
1011
101001
0100
D6.0
000
00110
011001
1011
011001
0100
D7.0
000
00111
111000
1011
000111
0100
D8.0
000
01000
111001
0100
000110
1011
D9.0
000
01001
100101
1011
100101
0100
D10.0
000
01010
010101
1011
010101
0100
D11.0
000
01011
110100
1011
110100
0100
D12.0
000
01100
001101
1011
001101
0100
D13.0
000
01101
101100
1011
101100
0100
D14.0
000
01110
011100
1011
011100
0100
D15.0
000
01111
010111
0100
101000
1011
D16.0
000
10000
011011
0100
100100
1011
D17.0
000
10001
100011
1011
100011
0100
D18.0
000
10010
010011
1011
010011
0100
D19.0
000
10011
110010
1011
110010
0100
D20.0
000
10100
001011
1011
001011
0100
D21.0
000
10101
101010
1011
101010
0100
D22.0
000
10110
011010
1011
011010
0100
D23.0
000
10111
111010
0100
000101
1011
D24.0
000
11000
110011
0100
001100
1011
D25.0
000
11001
100110
1011
100110
0100
D26.0
000
11010
010110
1011
010110
0100
D27.0
000
11011
110110
0100
001001
1011
D28.0
000
11100
001110
1011
001110
0100
D29.0
000
11101
101110
0100
010001
1011
D30.0
000
11110
011110
0100
100001
1011
D31.0
000
11111
101011
0100
010100
1011
23
CY7B923
CY7B933
Valid Data Characters (SC/D = LOW) (continued)
Data
Byte
Name
Bits
Current RD−
Current RD+
HGF
EDCBA
abcdei
fghj
abcdei
fghj
D0.1
001
00000
100111
1001
011000
1001
D1.1
001
00001
011101
1001
100010
1001
D2.1
001
00010
101101
1001
010010
1001
D3.1
001
00011
110001
1001
110001
1001
D4.1
001
00100
110101
1001
001010
1001
D5.1
001
00101
101001
1001
101001
1001
D6.1
001
00110
011001
1001
011001
1001
D7.1
001
00111
111000
1001
000111
1001
D8.1
001
01000
111001
1001
000110
1001
D9.1
001
01001
100101
1001
100101
1001
D10.1
001
01010
010101
1001
010101
1001
D11.1
001
01011
110100
1001
110100
1001
D12.1
001
01100
001101
1001
001101
1001
D13.1
001
01101
101100
1001
101100
1001
D14.1
001
01110
011100
1001
011100
1001
D15.1
001
01111
010111
1001
101000
1001
D16.1
001
10000
011011
1001
100100
1001
D17.1
001
10001
100011
1001
100011
1001
D18.1
001
10010
010011
1001
010011
1001
D19.1
001
10011
110010
1001
110010
1001
D20.1
001
10100
001011
1001
001011
1001
D21.1
001
10101
101010
1001
101010
1001
D22.1
001
10110
011010
1001
011010
1001
D23.1
001
10111
111010
1001
000101
1001
D24.1
001
11000
110011
1001
001100
1001
D25.1
001
11001
100110
1001
100110
1001
D26.1
001
11010
010110
1001
010110
1001
D27.1
001
11011
110110
1001
001001
1001
D28.1
001
11100
001110
1001
001110
1001
D29.1
001
11101
101110
1001
010001
1001
D30.1
001
11110
011110
1001
100001
1001
D31.1
001
11111
101011
1001
010100
1001
D0.2
010
00000
100111
0101
011000
0101
D1.2
010
00001
011101
0101
100010
0101
24
CY7B923
CY7B933
Valid Data Characters (SC/D = LOW) (continued)
Data
Byte
Name
Bits
Current RD−
Current RD+
HGF
EDCBA
abcdei
fghj
abcdei
fghj
D2.2
010
00010
101101
0101
010010
0101
D3.2
010
00011
110001
0101
110001
0101
D4.2
010
00100
110101
0101
001010
0101
D5.2
010
00101
101001
0101
101001
0101
D6.2
010
00110
011001
0101
011001
0101
D7.2
010
00111
111000
0101
000111
0101
D8.2
010
01000
111001
0101
000110
0101
D9.2
010
01001
100101
0101
100101
0101
D10.2
010
01010
010101
0101
010101
0101
D11.2
010
01011
110100
0101
110100
0101
D12.2
010
01100
001101
0101
001101
0101
D13.2
010
01101
101100
0101
101100
0101
D14.2
010
01110
011100
0101
011100
0101
D15.2
010
01111
010111
0101
101000
0101
D16.2
010
10000
011011
0101
100100
0101
D17.2
010
10001
100011
0101
100011
0101
D18.2
010
10010
010011
0101
010011
0101
D19.2
010
10011
110010
0101
110010
0101
D20.2
010
10100
001011
0101
001011
0101
D21.2
010
10101
101010
0101
101010
0101
D22.2
010
10110
011010
0101
011010
0101
D23.2
010
10111
111010
0101
000101
0101
D24.2
010
11000
110011
0101
001100
0101
D25.2
010
11001
100110
0101
100110
0101
D26.2
010
11010
010110
0101
010110
0101
D27.2
010
11011
110110
0101
001001
0101
D28.2
010
11100
001110
0101
001110
0101
D29.2
010
11101
101110
0101
010001
0101
D30.2
010
11110
011110
0101
100001
0101
D31.2
010
11111
101011
0101
010100
0101
25
CY7B923
CY7B933
Valid Data Characters (SC/D = LOW) (continued)
Data
Byte
Name
Bits
Current RD−
Current RD+
HGF
EDCBA
abcdei
fghj
abcdei
fghj
D0.3
011
00000
100111
0011
011000
1100
D1.3
011
00001
011101
0011
100010
1100
D2.3
011
00010
101101
0011
010010
1100
D3.3
011
00011
110001
1100
110001
0011
D4.3
011
00100
110101
0011
001010
1100
D5.3
011
00101
101001
1100
101001
0011
D6.3
011
00110
011001
1100
011001
0011
D7.3
011
00111
111000
1100
000111
0011
D8.3
011
01000
111001
0011
000110
1100
D9.3
011
01001
100101
1100
100101
0011
D10.3
011
01010
010101
1100
010101
0011
D11.3
011
01011
110100
1100
110100
0011
D12.3
011
01100
001101
1100
001101
0011
D13.3
011
01101
101100
1100
101100
0011
D14.3
011
01110
011100
1100
011100
0011
D15.3
011
01111
010111
0011
101000
1100
D16.3
011
10000
011011
0011
100100
1100
D17.3
011
10001
100011
1100
100011
0011
D18.3
011
10010
010011
1100
010011
0011
D19.3
011
10011
110010
1100
110010
0011
D20.3
011
10100
001011
1100
001011
0011
D21.3
011
10101
101010
1100
101010
0011
D22.3
011
10110
011010
1100
011010
0011
D23.3
011
10111
111010
0011
000101
1100
D24.3
011
11000
110011
0011
001100
1100
D25.3
011
11001
100110
1100
100110
0011
D26.3
011
11010
010110
1100
010110
0011
D27.3
011
11011
110110
0011
001001
1100
D28.3
011
11100
001110
1100
001110
0011
D29.3
011
11101
101110
0011
010001
1100
D30.3
011
11110
011110
0011
100001
1100
D31.3
011
11111
101011
0011
010100
1100
26
CY7B923
CY7B933
Valid Data Characters (SC/D = LOW) (continued)
Data
Byte
Name
Bits
Current RD−
Current RD+
HGF
EDCBA
abcdei
fghj
abcdei
fghj
D0.4
100
00000
100111
0010
011000
1101
D1.4
100
00001
011101
0010
100010
1101
D2.4
100
00010
101101
0010
010010
1101
D3.4
100
00011
110001
1101
110001
0010
D4.4
100
00100
110101
0010
001010
1101
D5.4
100
00101
101001
1101
101001
0010
D6.4
100
00110
011001
1101
011001
0010
D7.4
100
00111
111000
1101
000111
0010
D8.4
100
01000
111001
0010
000110
1101
D9.4
100
01001
100101
1101
100101
0010
D10.4
100
01010
010101
1101
010101
0010
D11.4
100
01011
110100
1101
110100
0010
D12.4
100
01100
001101
1101
001101
0010
D13.4
100
01101
101100
1101
101100
0010
D14.4
100
01110
011100
1101
011100
0010
D15.4
100
01111
010111
0010
101000
1101
D16.4
100
10000
011011
0010
100100
1101
D17.4
100
10001
100011
1101
100011
0010
D18.4
100
10010
010011
1101
010011
0010
D19.4
100
10011
110010
1101
110010
0010
D20.4
100
10100
001011
1101
001011
0010
D21.4
100
10101
101010
1101
101010
0010
D22.4
100
10110
011010
1101
011010
0010
D23.4
100
10111
111010
0010
000101
1101
D24.4
100
11000
110011
0010
001100
1101
D25.4
100
11001
100110
1101
100110
0010
D26.4
100
11010
010110
1101
010110
0010
D27.4
100
11011
110110
0010
001001
1101
D28.4
100
11100
001110
1101
001110
0010
D29.4
100
11101
101110
0010
010001
1101
D30.4
100
11110
011110
0010
100001
1101
D31.4
100
11111
101011
0010
010100
1101
27
CY7B923
CY7B933
Valid Data Characters (SC/D = LOW) (continued)
Data
Byte
Name
Bits
Current RD−
Current RD+
HGF
EDCBA
abcdei
fghj
abcdei
fghj
D0.5
101
00000
100111
1010
011000
1010
D1.5
101
00001
011101
1010
100010
1010
D2.5
101
00010
101101
1010
010010
1010
D3.5
101
00011
110001
1010
110001
1010
D4.5
101
00100
110101
1010
001010
1010
D5.5
101
00101
101001
1010
101001
1010
D6.5
101
00110
011001
1010
011001
1010
D7.5
101
00111
111000
1010
000111
1010
D8.5
101
01000
111001
1010
000110
1010
D9.5
101
01001
100101
1010
100101
1010
D10.5
101
01010
010101
1010
010101
1010
D11.5
101
01011
110100
1010
110100
1010
D12.5
101
01100
001101
1010
001101
1010
D13.5
101
01101
101100
1010
101100
1010
D14.5
101
01110
011100
1010
011100
1010
D15.5
101
01111
010111
1010
101000
1010
D16.5
101
10000
011011
1010
100100
1010
D17.5
101
10001
100011
1010
100011
1010
D18.5
101
10010
010011
1010
010011
1010
D19.5
101
10011
110010
1010
110010
1010
D20.5
101
10100
001011
1010
001011
1010
D21.5
101
10101
101010
1010
101010
1010
D22.5
101
10110
011010
1010
011010
1010
D23.5
101
10111
111010
1010
000101
1010
D24.5
101
11000
110011
1010
001100
1010
D25.5
101
11001
100110
1010
100110
1010
D26.5
101
11010
010110
1010
010110
1010
D27.5
101
11011
110110
1010
001001
1010
D28.5
101
11100
001110
1010
001110
1010
D29.5
101
11101
101110
1010
010001
1010
D30.5
101
11110
011110
1010
100001
1010
D31.5
101
11111
101011
1010
010100
1010
D0.6
110
00000
100111
0110
011000
0110
D1.6
110
00001
011101
0110
100010
0110
D2.6
110
00010
101101
0110
010010
0110
28
CY7B923
CY7B933
Valid Data Characters (SC/D = LOW) (continued)
Data
Byte
Name
Bits
Current RD−
Current RD+
HGF
EDCBA
abcdei
fghj
abcdei
fghj
D3.6
110
00011
110001
0110
110001
0110
D4.6
110
00100
110101
0110
001010
0110
D5.6
110
00101
101001
0110
101001
0110
D6.6
110
00110
011001
0110
011001
0110
D7.6
110
00111
111000
0110
000111
0110
D8.6
110
01000
111001
0110
000110
0110
D9.6
110
01001
100101
0110
100101
0110
D10.6
110
01010
010101
0110
010101
0110
D11.6
110
01011
110100
0110
110100
0110
D12.6
110
01100
001101
0110
001101
0110
D13.6
110
01101
101100
0110
101100
0110
D14.6
110
01110
011100
0110
011100
0110
D15.6
110
01111
010111
0110
101000
0110
D16.6
110
10000
011011
0110
100100
0110
D17.6
110
10001
100011
0110
100011
0110
D18.6
110
10010
010011
0110
010011
0110
D19.6
110
10011
110010
0110
110010
0110
D20.6
110
10100
001011
0110
001011
0110
D21.6
110
10101
101010
0110
101010
0110
D22.6
110
10110
011010
0110
011010
0110
D23.6
110
10111
111010
0110
000101
0110
D24.6
110
11000
110011
0110
001100
0110
D25.6
110
11001
100110
0110
100110
0110
D26.6
110
11010
010110
0110
010110
0110
D27.6
110
11011
110110
0110
001001
0110
D28.6
110
11100
001110
0110
001110
0110
D29.6
110
11101
101110
0110
010001
0110
D30.6
110
11110
011110
0110
100001
0110
D31.6
110
11111
101011
0110
010100
0110
29
CY7B923
CY7B933
Valid Data Characters (SC/D = LOW) (continued)
Data
Byte
Name
Bits
Current RD−
Current RD+
HGF
EDCBA
abcdei
fghj
abcdei
fghj
D0.7
111
00000
100111
0001
011000
1110
D1.7
111
00001
011101
0001
100010
1110
D2.7
111
00010
101101
0001
010010
1110
D3.7
111
00011
110001
1110
110001
0001
D4.7
111
00100
110101
0001
001010
1110
D5.7
111
00101
101001
1110
101001
0001
D6.7
111
00110
011001
1110
011001
0001
D7.7
111
00111
111000
1110
000111
0001
D8.7
111
01000
111001
0001
000110
1110
D9.7
111
01001
100101
1110
100101
0001
D10.7
111
01010
010101
1110
010101
0001
D11.7
111
01011
110100
1110
110100
1000
D12.7
111
01100
001101
1110
001101
0001
D13.7
111
01101
101100
1110
101100
1000
D14.7
111
01110
011100
1110
011100
1000
D15.7
111
01111
010111
0001
101000
1110
D16.7
111
10000
011011
0001
100100
1110
D17.7
111
10001
100011
0111
100011
0001
D18.7
111
10010
010011
0111
010011
0001
D19.7
111
10011
110010
1110
110010
0001
D20.7
111
10100
001011
0111
001011
0001
D21.7
111
10101
101010
1110
101010
0001
D22.7
111
10110
011010
1110
011010
0001
D23.7
111
10111
111010
0001
000101
1110
D24.7
111
11000
110011
0001
001100
1110
D25.7
111
11001
100110
1110
100110
0001
D26.7
111
11010
010110
1110
010110
0001
D27.7
111
11011
110110
0001
001001
1110
D28.7
111
11100
001110
1110
001110
0001
D29.7
111
11101
101110
0001
010001
1110
D30.7
111
11110
011110
0001
100001
1110
D31.7
111
11111
101011
0001
010100
1110
30
CY7B923
CY7B933
)
Valid Special Character Codes and Sequences (SC/D = HIGH)[23, 24]
Bits
S.C. Byte Name
S.C. Code Name
HGF
EDCBA
Current RD−
abcdei
fghj
Current RD+
abcdei
fghj
K28.0
C0.0
(C00)
000
00000
001111
0100
110000
1011
K28.1
C1.0
(C01)
000
00001
001111
1001
110000
0110
K28.2
C2.0
(C02)
000
00010
001111
0101
110000
1010
K28.3
C3.0
(C03)
000
00011
001111
0011
110000
1100
K28.4
C4.0
(C04)
000
00100
001111
0010
110000
1101
K28.5
C5.0
(C05)
000
00101
001111
1010
110000
0101
K28.6
C6.0
(C06)
000
00110
001111
0110
110000
1001
K28.7
C7.0
(C07)
000
00111
001111
1000
110000
0111
K23.7
C8.0
(C08)
000
01000
111010
1000
000101
0111
K27.7
C9.0
(C09)
000
01001
110110
1000
001001
0111
K29.7
C10.0
(C0A)
000
01010
101110
1000
010001
0111
K30.7
C11.0
(C0B)
000
01011
011110
1000
100001
0111
Idle
C0.1
(C20)
001
00000
−K28.5+,D21.4,D21.5,D21.5,repeat[25]
R_RDY
C1.1
(C21)
001
00001
−K28.5+,D21.4,D10.2,D10.2,repeat[26]
EOFxx
C2.1
(C22)
001
00010
−K28.5,Dn.xxx0[27]+K28.5,Dn.xxx1[27]
Follows K28.1 for ESCON Connect−SOF (Rx indication only)
C−SOF
C7.1
(C27)
001
00111
001111
1000
110000
0111
1000
110000
0111
Follows K28.5 for ESCON Passive−SOF (Rx indication only)
P−SOF
C7.2
(C47)
010
00111
001111
Code Rule Violation and SVS Tx Pattern
Exception
C0.7
(CE0)
111
00000
100111
1000[28]
011000
0111[28]
001111
1010[29]
110000
0101[30]
−K28.5
C1.7
(CE1)
111
00001
001111
1010[29]
+K28.5
C2.7
(CE2)
111
00010
110000
0101[30]
Running Disparity Violation Pattern
Exception
C4.7
(CE4)
111
00100
110111
0101[31]
001000
1010[31]
Notes:
23. All codes not shown are reserved.
24. Notation for Special Character Byte Name is consistent with Fibre Channel and ESCON naming conventions. Special Character Code Name is intended to
describe binary information present on I/O pins. Common usage for the name can either be in the form used for describing Data patterns (i.e., C0.0 through
C31.7), or in hex notation (i.e., Cnn where nn=the specified value between 00 and FF).
25. C0.1 = Transmit Negative K28.5 (−K28.5+) disregarding Current RD when input is held for only one byte time. If held longer, transmitter begins sending the
repeating transmit sequence −K28.5+, D21.4, D21.5, D21.5, (repeat all four bytes)... defined in X3.230 as the primitive signal “Idle word.” This Special
Character input must be held for four (4) byte times or multiples of four bytes or it will be truncated by the new data. The receiver will never output this Special
Character, since K28.5 is decoded as C5.0, C1.7, or C2.7, and the subsequent bytes are decoded as data.
26. C1.1 = Transmit Negative K28.5 (−K28.5+) disregarding Current RD when input is held for only one byte time. If held longer, transmitter begins sending the
repeating transmit sequence −K28.5+, D21.4, D10.2, D10.2,(repeat all four bytes)... defined in X3.230 as the primitive signal “Receiver_Ready (R_RDY).”
This Special Character input must be held for four (4) byte times or multiples of four bytes or it will be truncated by the new data.
The receiver will never output this Special Character, since K28.5 is decoded as C5.0, C1.7, or C2.7 and the subsequent bytes are decoded as data.
27. C2.1 = Transmit either −K28.5+ or +K28.5− as determined by Current RD and modify the Transmission Character that follows, by setting its least significant
bit to 1 or 0. If Current RD at the start of the following character is plus (+) the LSB is set to 0, and if Current RD is minus (−) the LSB becomes 1. This
modification allows construction of X3.230 “EOF” frame delimiters wherein the second data byte is determined by the Current RD.
For example, to send “EOFdt” the controller could issue the sequence C2.1−D21.4− D21.4−D21.4, and the HOTLink Transmitter will send either
K28.5−D21.4−D21.4−D21.4 or K28.5−D21.5− D21.4−D21.4 based on Current RD. Likewise to send “EOFdti” the controller could issue the sequence
C2.1−D10.4−D21.4−D21.4, and the HOTLink Transmitter will send either K28.5−D10.4−D21.4− D21.4 or K28.5−D10.5−D21.4− D21.4 based on Current RD.
The receiver will never output this Special Character, since K28.5 is decoded as C5.0, C1.7, or C2.7, and the subsequent bytes are decoded as data.
28. C0.7 = Transmit a deliberate code rule violation. The code chosen for this function follows the normal Running Disparity rul es. Transmission of this Special
Character has the same effect as asserting SVS = HIGH.
The receiver will only output this Special Character if the Transmission Character being decoded is not found in the tables.
31
CY7B923
CY7B933
Ordering Information
Speed
Standard
400
155
Speed
Standard
400
155
Ordering Code
Package
Name
Package Type
Operating
Range
CY7B923-JC
J64
28-Lead Plastic Leaded Chip Carrier
Commercial
CY7B923-JI
J64
28-Lead Plastic Leaded Chip Carrier
Industrial
CY7B923-SC
J64
28-Lead Small Outline IC
Commercial
CY7B923-LMB
L64
28-Square Leadless Chip Carrier
Military
CY7B923-400JC
J64
28-Lead Plastic Leaded Chip Carrier
Commercial
CY7B923-400JI
J64
28-Lead Plastic Leaded Chip Carrier
Industrial
CY7B923-155JC
J64
28-Lead Plastic Leaded Chip Carrier
Commercial
CY7B923-155JI
J64
28-Lead Plastic Leaded Chip Carrier
Industrial
Ordering Code
Package Name
Package Type
Operating
Range
CY7B933-JC
J64
28-Lead Plastic Leaded Chip Carrier
Commercial
CY7B933-JI
J64
28-Lead Plastic Leaded Chip Carrier
Industrial
CY7B933-SC
J64
28-Lead Small Outline IC
Commercial
CY7B933-LMB
L64
28-Square Leadless Chip Carrier
Military
CY7B933-400JC
J64
28-Lead Plastic Leaded Chip Carrier
Commercial
CY7B933-400JI
J64
28-Lead Plastic Leaded Chip Carrier
Industrial
CY7B933-155JC
J64
28-Lead Plastic Leaded Chip Carrier
Commercial
CY7B933-155JI
J64
28-Lead Plastic Leaded Chip Carrier
Industrial
Notes:
29. C1.7 = Transmit Negative K28.5 (−K28.5+) disregarding Current RD.
The receiver will only output this Special Character if K28.5 is received with the wrong running disparity. The receiver will output C1.7 if −K28.5 is received
with RD+, otherwise K28.5 is decoded as C5.0 or C2.7.
30. C2.7 = Transmit Positive K28.5 (+K28.5−) disregarding Current RD.
The receiver will only output this Special Character if K28.5 is received with the wrong running disparity. The receiver will output C2.7 if +K28.5 is received
with RD−, otherwise K28.5 is decoded as C5.0 or C1.7
31. C4.7 = Transmit a deliberate code rule violation to indicate a Running Disparity violation.
The receiver will only output this Special Character if the Transmission Character being decoded is found in the tables, but Running Disparity does not match.
This might indicate that an error occurred in a prior byte.
32
CY7B923
CY7B933
MILITARY SPECIFICATIONS
Group A Subgroup Testing
Switching Characteristics
Parameter
Subgroup
tCKW
9, 10, 11
tB
9, 10, 11
1, 2, 3
tCPWH
9, 10, 11
VOLT
1, 2, 3
tCPWL
9, 10, 11
VOHE
1, 2
tSD
9, 10, 11
VOLE
1, 2, 3
tHD
9, 10, 11
VODIF
1, 2, 3
tSENP
9, 10, 11
IOST
1, 2, 3
tHENP
9, 10, 11
VIHT
1, 2, 3
tPDR
9, 10, 11
VILT
1, 2, 3
tPPWH
9, 10, 11
VIHE
1, 2, 3
tPDF
9, 10, 11
VILE
1, 2, 3
tRISE
9, 10, 11
IIHT
1, 2, 3
tFALL
9, 10, 11
IILT
1, 2, 3
tCKR
9, 10, 11
IIHE
1, 2, 3
tCPRH
9, 10, 11
IILE
1, 2, 3
tCPRL
9, 10, 11
ICC
1, 2, 3
tRH
9, 10, 11
VDIFF
1, 2, 3
tPRF
9, 10, 11
VIHH
1, 2, 3
tPRH
9, 10, 11
VILL
1, 2, 3
tA
9, 10, 11
tROH
9, 10, 11
tH
9, 10, 11
tCKX
9, 10, 11
tCPXH
9, 10, 11
tCPXL
9, 10, 11
tDS
9, 10, 11
DC Characteristics
Parameter
VOHT
Subgroup
Document #: 38−00189−H
33
CY7B923
CY7B933
Package Diagrams
28-Lead Plastic Leaded Chip Carrier J64
28-Square Leadless Chip Carrier L64
MIL−STD−1835 C−4
34
CY7B923
CY7B933
Package Diagrams (continued)
28-Lead (300-Mil) Molded SOIC S21
© Cypress Semiconductor Corporation, 1997. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use
of any circuitry other than circuitry embodied in a Cypress Semiconductor product. Nor does it convey or imply any license under patent or other rights. Cypress Semiconductor does not authorize
its products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress
Semiconductor products in life-support systems application implies that the manufacturer assumes all risk of such use and in doing so indemnifies Cypress Semiconductor against all charges.