DS3112
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6.3 T2/E2/G.747 Framer Status And Interrupt Register Description
Register Name:
T2E2SR1
Register Description:
T2/E2 Status Register 1
Register Address:
34h
Bit #
7
6
5
Name
IELOF
LOF7
LOF6
Default
0
-
-
Bit #
15
14
13
Name
IEAIS
AIS7
AIS6
Default
0
-
-
Note:
See Figure 6.3A for details on the signal flow for the status bits in the T2E2SR1 register.
Bits that are underlined are read-only; all other bits are read-write.
Bits 0 to 6/Loss Of Frame Occurrence (LOFn when n = 1 to 7).
This latched read-only alarm-status
bit will be set to a one each time the corresponding T2/E2/G.747 framer detects a Loss Of Frame (LOF).
This bit will be cleared when read unless a LOF condition still exists in that T2/E2/G.747 framer. A
change in state of the LOF in one or more of the T2/E2/G.747 framers can cause the T2E2SR1 status bit
(in the MSR register) to be set and a hardware interrupt to occur if the IELOF bit is set to a one and the
T2E2SR1 bit in the Interrupt Mask for MSR (IMSR) register is set to a one (Figure 6.3A). The interrupt
will be allowed to clear when this bit is read. The LOF alarm criteria is described in Tables 6.3A, 6.3B,
and 6.3C. In the E3 mode, LOF5 to LOF7 (bits 4 to 6) are meaningless and should be ignored.
Bit 7/Interrupt Enable for Loss of Frame Occurrence (IELOF).
This bit should be set to one if the
host wishes to have T2/E2/G.747 LOF occurrences cause a hardware interrupt or the setting of the
T2E2SR1 status bit in the MSR register (Figure 6.3A). The T2E2SR1 bit in the Interrupt Mask for the
Master Status Register (IMSR) must also be set to one for an interrupt to occur.
0 = interrupt masked
1 = interrupt unmasked
Bits 8 to 14/Alarm Indication Signal Detected (AISn when n = 1 to 7).
This latched read-only alarm-
status bit will be set to a one each time the corresponding T2/E2/G.747 framer detects an incoming AIS
alarm. This bit will be cleared when read unless the AIS alarm still exists in that T2/E2/G.747 framer. A
change in state of the AIS detector in one or more of the T2/E2/G.747 framers can cause the T2E2SR1
status bit (in the MSR register) to be set and a hardware interrupt to occur if the IEAIS bit is set to a one
and the T2E2SR1 bit in the Interrupt Mask for MSR (IMSR) register is set to a one (Figure 6.3A). The
interrupt will be allowed to clear when this bit is read. The AIS alarm criteria is described in Tables 6.3A,
6.3B, and 6.3C. In the E3 mode, AIS5 to AIS7 (bits 4 to 6) are meaningless and should be ignored.
Bit 15/Interrupt Enable for Alarm Indication Signal (IEAIS).
This bit should be set to one if the host
wishes to have T2/E2/G.747 AIS detection occurrences cause a hardware interrupt or the setting of the
T2E2SR1 status bit in the MSR register (Figure 6.3A). The T2E2SR1 bit in the Interrupt Mask for the
Master Status Register (IMSR) must also be set to one for an interrupt to occur.
0 = interrupt masked
1 = interrupt unmasked
4
3
2
1
0
LOF5
-
LOF4
-
LOF3
-
LOF2
-
LOF1
-
12
AIS5
-
11
AIS4
-
10
AIS3
-
9
8
AIS2
-
AIS1
-