XRT79L71 Datasheet, PDF (215/441 Pages) Exar Corporation – 1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC

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PRELIMINARY
1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC
TRANSMIT E3, ITU-T G.751 RELATED REGISTERS
TXE3 CONFIGURATION REGISTER - G.751 (DIRECT ADDRESS = 0X1130)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
TxBIP-4
Enable
TxASrcSel[1:0]
TxNSrcSel[1:0]
TxAIS Enable
BIT 1
TxLOS
Enable
R/W
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
0
0
0
0
XRT79L71
REV. P1.0.3
BIT 0
TxFAS
Source
Sel
R/W
0
BIT NUMBER
NAME
7
TxBIP-4 Enable
6-5
TxASrcSel[1:0]
4-3
TxNSrcSel[1:0]
TYPE
R/W
R/W
DESCRIPTION
Transmit BIP-4 Enable:
This READ/WRITE bit-field permits the user to configure the
Frame Generator block to do the following:
a. Compute the BIP-4 value over a given E3 frame.
b. Insert this BIP-4 value into the last nibble-field within the
very next E3 frame.0 - Does not configure this option. In
this case, the last nibble (of each "outbound" E3 frame)
will contain payload data.1 - Configures the Frame
Generator block to compute and insert the BIP-4 value.
Transmit A Bit Source Select[1:0]:
These two READ/WRITE bit-fields permit the user to specify the
source or type of data that is being carried via the "A" bits, within
each "outbound" E3 data stream, as indicated below.
TxASrcSel[1:0]
0
0
0
1
1
0
1
1
Resulting Source of A Bit
The "TxA" bit-field, within the "TxE3
Service Bit" register (Direct Address =
0x1135)
Not Valid - Do not use.
The "A" bit is sourced via the "Payload
Data Input Interface" block. This is
discussed in greater detail in Section _.
The Com panion Fram e Synchronizer
block. In this case, the A bit will transm it
the FEBE indicator to the rem ote term inal
equipm ent. The A bit will be set to "1"
when the com panion Fram e Synchronizer
detects a BIP-4 error, and will be set to "0"
when the Fram e Synchronizer detects un-
erred E3 fram es.
R/W Transmit N Bit Source Select[1:0]:
These two READ/WRITE bit-fields permit the user to specify the
source or type of data that is being carried via the "N" bits, within
each "outbound" E3 data stream, as indicated below.
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