XRT79L71 Datasheet, PDF (176/441 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
RXE3 LAPD CONTROL REGISTER - G.832 (DIRECT ADDRESS = 0X1118)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
RxLAPD
Any
Unused
DL from NR Byte RxLAPD Enable
RxLAPD
RxLAPD
Interrupt Enable Interrupt Status
R/W
R/O
R/O
R/O
R/W
R/W
R/W
RUR
0
0
0
0
0
0
0
0
BIT NUMBER
NAME
7
RxLAPD Any
6-4
3
Unused
DL from NR Byte
TYPE
R/W
R/O
R/W
DESCRIPTION
Receive LAPD - Any kind:
This READ/WRITE bit-field permits the user to configure the
LAPD Receiver to receive any kind of LAPD Message (or HDLC
Message) with a size of 82 bytes or less. If the user implements
this option, then the LAPD Receiver will be capable of receiving
any kind of HDLC Message (with any value of header bytes).
The only restriction is that the size of the HDLC Message must
not exceed 82 bytes.
0 - Does not invoke this "Any Kind of HDLC Message" feature.
In this case, the LAPD Receiver will only receive HDLC Mes-
sages that contains the Bellcore GR-499-CORE values for SAPI
and TEI.
1-Invokes this "Any Kind of HDLC Message" feature. In this
case, the LAPD Receiver will be able to receive HDLC Mes-
sages that contain any header byte values.
NOTES:
1. This bit-field is ignored if the Frame Synchronizer block
is by-passed.
2. The user can determine the size (or byte count) fo the
most recently received LAPD/PMDL Message, by
reading the contents of the "RxLAPD Byte Count"
Register (Direct Address = 0x1184).
PMDL in NR Byte Select:
This READ/WRITE bit-field permits the user to configure the
LAPD Receiver to extract out the PMDL data from the NR or GC
byte, within the incoming E3 data stream.
0 - The LAPD Receiver will extract PMDL information from the
GC byte, within the incoming E3 data stream.
1 - The LAPD Receiver will extract PMDL information from the
NR byte, within the incoming E3 data stream.
NOTE: This bit-field is ignored if the Frame Synchronizer block is
by-passed.
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