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STANDARD PRODUCT
PMC-Sierra, Inc.
PM6344 EQUAD
PMC-951013
ISSUE 5
QUADRUPLE E1 FRAMER
132
Register 034H, 0B4H, 134H, 1B4H: XFDL Block Configuration
Bit
Type
Function
Default
Bit 7
Unused
X
Bit 6
Unused
X
Bit 5
Unused
X
Bit 4
R/W
EOM
0
Bit 3
R/W
INTE
0
Bit 2
R/W
ABT
0
Bit 1
R/W
CRC
0
Bit 0
R/W
EN
0
EOM:
The EOM bit indicates that the last byte of data written in the XFDL Transmit
Data register is the end of the present data packet. If the CRC bit is set then
the 16-bit FCS word is appended to the last data byte transmitted and a
continuous stream of flags is generated. The EOM bit is automatically cleared
before transmission of the next data packet begins.
INTE:
The INTE bit enables the generation of an interrupt via the TDLINT[x] output.
Setting the INTE bit to logic 1 enables the generation of an interrupt; setting
INTE to logic 0 disables the generation of an interrupt. If the TDLINTE bit is
also set to logic 1 in the Datalink Options register, the interrupt generated on
the TDLINT[x] output is also generated on the microprocessor INTB pin.
ABT:
The Abort (ABT) bit controls the sending of the 7 consecutive ones HDLC
abort code. Setting the ABT bit to a logic 1 causes the 11111110 code to be
transmitted after the last byte from the XFDL Transmit Data Register is
transmitted. Aborts are continuously sent until this bit is reset to a logic 0.
CRC:
The CRC enable bit controls the generation of the ITU-T-CRC frame check
sequence (FCS). Setting the CRC bit to logic 1 enables the ITU-T-CRC
generator and the appends the 16 bit FCS to the end of each message.
When the CRC bit is set to logic 0, the FCS is not appended to the end of the