XRT79L71 Datasheet, PDF (218/441 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
TXE3 LAPD STATUS/INTERRUPT REGISTER - G.751 (DIRECT ADDRESS = 0X1134)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
Unused
TxDL Start TxDL Busy
TxLAPD
Interrupt
Enable
R/O
R/O
R/O
R/O
R/W
R/O
R/W
0
0
0
0
0
0
0
BIT 0
TxLAPD
Interrupt
Status
RUR
0
BIT NUMBER
NAME
7-4
Unused
3
TxDL Start
2
TxDL Busy
1
TxLAPD Interrupt Enable
0
TxLAPD Interrupt Status
TYPE
R/O
R/W
R/O
R/W
RUR
DESCRIPTION
Transmit LAPD Message Command:
A "0" to "1" transition, within this bit-field commands the LAPD
Transmitter to begin the following activities:
• Reading out the contents of the Transmit LAPD Message
Buffer.
• Zero-Stuffing of this data
• FCS Calculation and Insertion
• Fragmentation of this composite PMDL Message, and
insertion into the "DL" bit-fields, within each outbound DS3
frame.
Transmit LAPD Controller Busy Indicator:
This "READ-ONLY" bit-field indicates whether or not the Transmit
LAPD Controller is currently busy transmitting a PMDL Message
to the remote terminal equipment. The user can continuously
poll this bit-field in order to check for completion of transmission
of the LAPD/PMDL Message.
0 - LAPD Transmitter is NOT busy transmitting a PMDL Mes-
sage.
1 - LAPD Transmitter is currently busy transmitting a PMDL Mes-
sage.
Transmit LAPD Interrupt Enable:
This READ/WRITE bit-field permits the user to either enable or
disable the "Transmit LAPD Interrupt". If the user enables this
interrupt, then the channel will generate an interrupt anytime the
LAPD Transmitter has completed its transmission of a given
LAPD/PMDL Message to the remote terminal.
0 - Disables Transmit LAPD Interrupt.
1 - Enables Transmit LAPD Interrupt.
Transmit LAPD Interrupt Status:
This RESET-upon-READ bit-field indicates whether or not the
"Transmit LAPD Interrupt" has occurred since the last read of
this register.
0 - Transmit LAPD Interrupt has NOT occurred since the last
read of this register.
1 - Transmit LAPD Interrupt has occurred since the last read of
this register.
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