XRT79L71_1 Datasheet, PDF (170/434 Pages) Exar Corporation – 1-CHANNEL DS3/E3 ATM UNI/PPP/CLEAR-CHANNEL FRAMER IC -

XRT79L71
1-CHANNEL DS3/E3 ATM UNI/PPP/CLEAR-CHANNEL FRAMER IC - REGISTER/MAP DESCRIPTION
REV. 1.0.0
BIT NUMBER
NAME
0
TxFAS Source Sel
TYPE
R/W
DESCRIPTION
Transmit FAS Source Select:
This READ/WRITE bit-field permits the user to specify the
source of the FAS (Framing Alignment Signal), to be used in the
Outbound E3 data-stream, as indicated below.
0 - Configures the Transmit E3 Framer block to internally gener-
ate and insert the FAS bits within the outbound E3 data-stream.
1 - Configures the Transmit E3 Framer block to accept the FAS
bits from "up-stream" circuitry (via the Transmit Payload Data
Input Interface block) and to insert this data into the outbound E3
data-stream. This is discussed in greater detail in Section _.
Transmit E3 LAPD Configuration Register - G.751 (Address = 0x1133)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
Unused
Auto
Retransmit
Reserved
R/O
R/O
R/O
R/O
R/W
R/O
0
0
0
0
1
0
BIT 1
Transmit
LAPD
Message
Length
R/W
0
BIT 0
Transmit
LAPD
Enable
R/W
0
BIT NUMBER
NAME
7-4
Unused
3
Auto Retransmit
2
Reserved
TYPE
R/O
R/W
R/O
DESCRIPTION
Auto-Retransmit of LAPD Message:
This READ/WRITE bit-field permits the user to configure the
Transmit LAPD Controller block to transmit PMDL messages,
repeatedly at one-second intervals. Once the user enables this
feature, and then commands the Transmit LAPD Controller block
to transmit a given PMDL Message, the Transmit LAPD Control-
ler block will then proceed to transmit this PMDL Message
(based upon the contents within the Transmit LAPD Message
Buffer) repeatedly at one-second intervals.
0 - Disables the Auto-Retransmit Feature. In this case, the
Transmit LAPD Controller block will transmit this PMDL Mes-
sage will only be transmitted once, afterwards the Transmit
LAPD Controller block will proceed to transmit a continuous
stream of Flag Sequence octets (0x7E) via the DL bits, within
each output DS3 frame. No more PMDL Messages will be trans-
mitted until the user commands another transmission.
1 - Enables the Auto-Retransmit Feature.In this case, the Trans-
mit LAPD Controller block will transmit PMDL messages (based
upon the contents within the Transmit LAPD Message Buffer)
repeatedly at one-second intervals.
NOTE: This bit-field is ignored if the Transmit LAPD Controller
block is disabled.
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