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XRT79L71
PRELIMINARY
547
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
REV. P2.0.0
Once the user has executed these three steps, then the Receive SSM Controller block will be configured to
generate an interrupt request, anytime the Receive SSM Controller block declares the "SSM Out-of-Sequence"
condition within the incoming E3 data-stream.
Servicing the "SSM Out-of-Sequence" Interrupt
If the "SSM Out-of-Sequence" Interrupt has been enabled, and if the XRT79L71 does generate the "SSM Out-
of Sequence" Interrupt, then the user must service this particular interrupt by executing the following steps.
STEP 1 - Determine which kind of interrupt has been requested as the "Operational Block" Level
This is accomplished by reading out the contents of both the "Operation Interrupt Status Registers - Byte 1"
and "Byte 0" registers. The bit-format for each of these registers is presented below.
NOTE: Since this particular interrupt is the "SSM Out-of-Sequence" Interrupt, then Bit 2 (DS3/E3 Framer Block Interrupt
Status) within the "Operation Interrupt Status Register - Byte 1" Register will be set to "1" as indicated above.
Receive E3 Interrupt Enable Register # 1 - G.832 (Address = 0x1112)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Unused
Change in
SSM MSG
Interrupt
Enable
SSM OOS
Interrupt
Enable
COFA
Interrupt
Enable
Change in
OOF State
Interrupt
Enable
Change in
LOF State
Interrupt
Enable
Change in
LOS State
Interrupt
Enable
Change in
AIS State
Interrupt
Enable
R/O
R/W
0
1
0
Operation Interrupt Status Register - Byte 1 (Address = 0x0112)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Unused
DS3/E3
LIU/JA
Block
Interrupt
Status
DS3/E3
Framer
Block
Interrupt
Status
Unused
R/O
0
1
0
Operation Interrupt Status Register - Byte 0 (Address = 0x0113)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Receive
UTOPIA/
POS-PHY
Interface
Block
Interrupt
Status
Unused
Receive ATM
Cell/PPP
Processor
Block Inter-
rupt Status
Transmit
UTOPIA/
POS-PHY
Interface
Block
nterrupt
Status
Unused
Transmit
ATM
Cell/PPP
Processor
Block
Interrupt
Status
R/O
0