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 4 3 2 1 0
Name IELOF
LOF7
LOF6
LOF5
LOF4
LOF3
LOF2
LOF1
Default
0 - - - - - - -
Bit
# 15 14 13 12 11 10 9 8
Name IEAIS
AIS7
AIS6
AIS5
AIS4
AIS3
AIS2
AIS1
Default
0 - - - - - - -
Note: See
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 6-1
). The interrupt will be allowed to clear when this bit is read. The LOF
alarm criteria are described in
, and
Table 6-3
. 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 (
). 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 6-1
). The interrupt will be allowed to clear when this bit is read. The
AIS alarm criteria is described in
, and
Table 6-3
. 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 6-1
). 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