XRT79L71 Datasheet, PDF (352/441 Pages) Exar Corporation – 1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC

XRT79L71
REV. P1.0.3
PRELIMINARY
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1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC
RECEIVE PPP PACKET PROCESSOR BLOCK (PPP APPLICATIONS ONLY)
RECEIVE PPP PACKET PROCESSOR BLOCK - RECEIVE PPP CONTROL REGISTER (ADDRESS =
0X1703)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Unused
Receive
CRC-32/
CRC-16*
RxFIFO Over-
flow ABORT
Enable
Unused
De-Scramble Delete FCS Receive PPP
Enable from Incoming Packet Pro-
Packet cessor Block
Enable
R/O
R/O
R/W
R/W
R/O
R/W
R/W
R/W
0
0
0
0
0
0
0
0
BIT NUMBER
NAME
7-6
Unused
5
Receive CRC-32/CRC-
16*
4
RxFIFO Overflow ABORT
Enable
3
Unused
2
Descramble Enable
1
Delete FCS from Incom-
ing Packet
0
Receive PPP Packet Pro-
cessor Block Enable
TYPE
R/O
R/W
R/W
R/O
R/W
R/W
R/W
DESCRIPTION
Receive CRC-32/CRC-16* Select:
This READ/WRITE bit-field permits the user to configure the
Receive PPP Packet Processor block to either compute and ver-
ify a CRC-32 or CRC-16 within the incoming PPP packet-stream.
0 - Configures the Receive PPP Packet Processor block to com-
pute and verify a CRC-16 value within each incoming PPP
packet.
1 - Configures the Receive PPP Packet Processor block to com-
pute and verify a CRC-32 value within each incoming PPP
packet.
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