Cypress CYV15G0404DXB manual Use of the Tables for Generating Transmission Characters, Hex Value

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CYV15G0404DXB

mission of any transmission character, the transmitter selects the proper version of the transmission character based on the current running disparity value, and the transmitter calculates 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.

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 decides whether the transmission character is valid or invalid according to the following rules and tables and calculates a new value for its running disparity based on the contents of the received character.

The following rules for running disparity are used to calculate the new running disparity value for transmission characters that have been transmitted and received.

Running disparity for a transmission character is calculated from subblocks, where the first six bits (abcdei) form one subblock and the second four bits (fghj) form the other subblock. Running disparity at the beginning of the 6-bit subblock is the running disparity at the end of the previous transmission character. running disparity at the beginning of the 4-bit subblock is the running disparity at the end of the 6-bit subblock. Running disparity at the end of the transmission character is the running disparity at the end of the 4-bit subblock.

Running disparity for the subblocks is calculated as follows:

1.Running disparity at the end of any subblock is positive if the subblock contains more ones than zeros. It is also positive at the end of the 6-bit subblock if the 6-bit subblock is 000111, and it is positive at the end of the 4-bit subblock if the 4-bit subblock is 0011.

2.Running disparity at the end of any subblock is negative if the subblock contains more zeros than ones. It is also negative at the end of the 6-bit subblock if the 6-bit subblock is 111000, and it is negative at the end of the 4-bit subblock if the 4-bit subblock is 1100.

3.Otherwise, running disparity at the end of the subblock is the same as at the beginning of the subblock.

Use of the Tables for Generating Transmission Characters

The appropriate entry in Table 14 for the valid data byte or Table 15 for Special Character byte identify which transmission character is generated. The current value of the transmitter’s running disparity is used to select the transmission character from its corresponding column. For each transmission character

Table 13. Code Violations Resulting from Prior Errors

transmitted, a new value of the running disparity is calculated. This new value is used as the transmitter’s current running disparity for the next valid data byte or Special Character byte encoded and transmitted. Table 12 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 is 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 a code violation. Independent of the transmission character’s validity, the received transmission character is used to calculate a new value of running disparity. The new value is used as the receiver’s current running disparity for the next received trans- mission character.

Table 12. Valid Transmission Characters

Data

Byte Name

DIN or QOUT

Hex Value

765

43210

 

 

D0.0

000

00000

00

D1.0

000

00001

01

D2.0

000

00010

02

.

.

.

.

.

.

.

.

D5.2

010

00101

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 12 shows an example of this behavior.

 

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

+

 

 

 

 

 

 

 

 

Document #: 38-02097 Rev. *B

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Contents Functional Description FeaturesCypress Semiconductor Corporation 198 Champion Court Phase Elasticity Align Buffer Encoder Decoder 8B/10B Framer CYV15G0404DXB Transceiver Logic Block DiagramPhase-Align rBuffe Transmit Path Block DiagramBist Lfsr PLL = Internal Signal Device Configuration and Control BlockDevice Configura Tion and Control Interface Pin Configuration Top View Pin Configuration Bottom View Pin Definitions CYV15G0404DXB Quad HOTLink II Transceiver Transmit Path Clock SignalsStatus Signals Name Characteristics Signal DescriptionReceive Path Clock Signals Device Control SignalsUse Local Clock . When Device Configuration and Control Bus Signals Link Fault Indication OutputControl Write Enable . Reframe Mode SelectCYV15G0404DXB Transmit Data Path CYV15G0404DXB HOTLink II OperationData Encoding EncoderTransmit Modes Transmit BistTransmit PLL Clock Multiplier Serial Output Drivers Signal Detect/Link FaultCYV15G0404DXB Receive Data Path Serial Line ReceiversReclocker Clock/Data RecoveryDeserializer/Framer Receive Bist Operation 10B/8B Decoder BlockBits Detected FramerDevice Reset State Power ControlOutput Bus Receive Elasticity BufferOutput Register Bit Assignments Signal Name Device Configuration and Control InterfaceDecoder Bypass Mode Signal Name Bus Weight Bit Name DECBYPx = Decbyp =Name Signal Description Device Configuration and Control Latch DescriptionsRxckselb RxckselaRxckselc RxckseldTxrateb TxrateaTxratec TxratedDevice Control Latch Configuration Table Device Configuration StrategyRequired step Jtag SupportLevel Select Inputs Running disparity error . The character onNormal character received . The valid Data Receive Elasticity buffer underrun/overrunBisterror Bistdatacompare 000 / BistcommandcompareBiststart RX PLLPower Up Requirements CYV15G0404DXB DC Electrical CharacteristicsMaximum Ratings Operating RangeAC Test Loads and Waveforms Power Supply TypCML Output Test Load Lvttl Output Test Load18Receiver Lvttl Switching Characteristics Over the Operating CYV15G0404DXB AC Electrical CharacteristicsREFCLKx Switching Characteristics Over the Operating Range Parameter Description Min Max UnitJtag Test Clock Characteristics Over the Operating Range Bus Configuration Write Timing Characteristics OverTransmit Serial Outputs and TX PLL Characteristics Over DeviceCapacitance20 CYV15G0404DXB HOTLink II Transmitter Switching WaveformsTransmit Interface Write Timing REFCLKx selected TXRATEx = Parameter Description Test Conditions Max UnitWrite Timing REFCLKx selected Transmit InterfaceTXDx70 TXCTx10REFCLKx RXDx70, RXSTx20 TXERRx36 Bus Configuration Write Timing Reset Lvttl in PU VCC PowerCML Lvttl in PUTXDB6 Lvttl RXDC7 Lvttl OUTTXDC0 Lvttl RXDC4 Lvttl OUTNotation Conventions X3.230 Codes and Notation Conventions8B/10B Transmission Code Transmission OrderUse of the Tables for Generating Transmission Characters Code Violations Resulting from Prior ErrorsValid Transmission Characters Data Byte Name Hex ValueAbcdei fghj Abcdei fghj NameData Bits Current RD Current RD+ Byte Name CYV15G0404DXB CYV15G0404DXB Code Rule Violation and SVS Tx Pattern End of Frame SequenceViolation Pattern Ordering Information Package DiagramCYV15G0404DXB-BGC CYV15G0404DXB-BGIAGT New Data SheetUKK/VED Methods to implement it
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