XRT79L71_1 Datasheet, PDF (176/434 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
Transmit E3 LAPD Configuration Register - G.832 (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
1
Transmit LAPD Message
Length
TYPE
R/O
R/W
R/O
R/W
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 only transmit this PMDL
Message once. Afterwards the Transmit LAPD Controller block
will proceed to transmit a continuous stream of Flag Sequence
octets (0x7E) via either the NR or GC bytes, within each output
E3 frame. The Transmit LAPD Controller block will not transmit
any more PMDL Messages 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.
Transmit LAPD Message Length Select:
This READ/WRITE bit-field permits the user to specify the length
of the payload data within the outbound LAPD/PMDL Message,
as indicated below.
0 - Configures the Transmit LAPD Controller block to transmit a
LAPD/PMDL message that has a payload data size of 76 bytes.
1 - Configures the Transmit LAPD Controller block to transmit a
LAPD/PMDL message that has a payload data size of 82 bytes.
NOTE: This bit-field is ignored if the Transmit LAPD Controller
block is disabled.
167