XRT74L73 Datasheet, PDF (284/488 Pages) Exar Corporation – 3 CHANNEL, ATM UNI/PPP DS3/E3 FRAMING CONTROLLER

XRT74L73
3 CHANNEL, ATM UNI/PPP DS3/E3 FRAMING CONTROLLER
REV. P1.0.1
PRELIMINARY
RXDS3 FEAC INTERRUPT ENABLE/STATUS REGISTER (ADDRESS = 0X17)
BIT 7
BIT 6
Not Used
BIT 5
BIT 4
FEAC Valid
BIT 3
RxFEAC
Remove
Interrupt
Enable
BIT 2
RxFEAC
Remove
Interrupt
Status
RO
RO
RO
RO
R/W
RUR
0
0
0
0
0
0
BIT 1
RxFEAC
Valid
Interrupt
Enable
R/W
X
BIT 0
RxFEAC
Valid
Interrupt
Status
RUR
0
Setting this bit-field to “1” enables this interrupt. Con-
versely, setting this bit-field to “0” disables this inter-
rupt.
Servicing the Receive FEAC Message - Validation
Interrupt.
Whenever the XRT74L73 Framer IC generates this
interrupt, it will do the following.
• It will assert the Interrupt Request output pin (INT)
by driving it "Low".
• It will set Bit 0 (RxFEAC Valid Interrupt Status),
within the RxDS3 FEAC Interrupt Enable/Status
Register to “1”, as indicated below.
RXDS3 FEAC INTERRUPT ENABLE/STATUS REGISTER (ADDRESS = 0X17)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Not Used
FEAC Valid
RxFEAC
Remove
Interrupt
Enable
RxFEAC
Remove
Interrupt
Status
RxFEAC
Valid
Interrupt
Enable
RxFEAC
Valid
Interrupt
Status
RO
RO
RO
RO
R/W
RUR
R/W
RUR
0
0
0
0
0
0
1
1
• It will write the contents of this validated FEAC
Message into the Rx DS3 FEAC Register, as indi-
cated below.
RXDS3 FEAC REGISTER (ADDRESS = 0X16)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
Not Used
RxFEAC[5:0]
RO
RO
RO
RO
R/O
0
0
0
0
0
BIT 2
R/O
0
BIT 1
R/O
0
BIT 0
Not Used
R/O
0
Whenever the Terminal Equipment encounters the
Receive FEAC Message - Validation Interrupt, then it
should do the following.
• It should read the contents of the High RxDS3
FEAC Register, and respond accordingly.
4.3.6.2.10 The Receive FEAC Message -
Removal Interrupt
if the Receive FEAC Message - Removal Interrupt is
enabled, then the XRT74L73 Framer IC will generate
an interrupt any time the High Receive FEAC Proces-
sor removes a new FEAC (Far-End Alarm & Control)
Message.
In particular, the Receive FEAC Processor will re-
move a FEAC Message, it has received a different
FEAC Message (from the most recently validated
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