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DS2154
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ALARM CRITERIA Table 4–1
ALARM
SET CRITERIA
CLEAR CRITERIA
ITU
SPEC.
RSA1
(receive signaling
all ones)
over 16 consecutive frames (one full
MF) timeslot 16 contains less than
three zeros
over 16 consecutive frames (one full
MF) timeslot 16 contains three or
more zeros
G.732
4.2
RSA0
(receive signaling
all zeros)
over 16 consecutive frames (one full
MF) timeslot 16 contains all zeros
over 16 consecutive frames (one full
MF) timeslot 16 contains at least a
single one
G.732
5.2
RDMA
(receive distant
multiframe alarm)
bit 6 in timeslot 16 of frame 0 set to
one for two consecutive MF
bit 6 in timeslot 16 of frame 0 set to
zero for a two consecutive MF
O.162
2.1.5
RUA1
(receive unframed
all ones)
less than three zeros in two frames
(512 bits)
more than two zeros in two frames
(512 bits)
O.162
1.6.1.2
RRA
(receive remote
alarm)
bit 3 of non–align frame set to one for
three consecutive occasions
bit 3 of non–align frame set to zero for
three consecutive occasions
O.162
2.1.4
RCL
(receive carrier
loss)
255 (or 2048) consecutive zeros
received
in 255–bit times, at least 32 ones are
received
G.775 /
G.962
SR2: STATUS REGISTER 2 (Address=07 Hex)
(MSB)
(LSB)
RMF
RAF
TMF
SEC
TAF
LOTC
RCMF
TSLIP
SYMBOL
POSITION
NAME AND DESCRIPTION
RMF
SR2.7
Receive CAS Multiframe. Set every 2 ms (regardless if CAS signaling is
enabled or not) on receive multiframe boundaries. Used to alert the host
that signaling data is available.
RAF
SR2.6
Receive Align Frame. Set every 250
µ
s at the beginning of align frames.
Used to alert the host that Si and Sa bits are available in the RAF and RNAF
registers.
TMF
SR2.5
Transmit Multiframe. Set every 2 ms (regardless if CRC4 is enabled) on
transmit multiframe boundaries. Used to alert the host that signaling data
needs to be updated.
SEC
SR2.4
One Second Timer. Set on increments of one second based on RCLK. If
CCR2.7=1, then this bit will be set every 62.5 ms instead of once a second.
TAF
SR2.3
Transmit Align Frame. Set every 250
µ
s at the beginning of align frames.
Used to alert the host that the TAF and TNAF registers need to be updated.
LOTC
SR2.2
Loss of Transmit Clock. Set when the TCLK pin has not transitioned for
one channel time (or 3.9
µ
s). Will force the LOTC pin high if enabled via
TCR2.0.
RCMF
SR2.1
Receive CRC4 Multiframe. Set on CRC4 multiframe boundaries; will con-
tinue to be set every 2 ms on an arbitrary boundary if CRC4 is disabled.
TSLIP
SR2.0
Transmit Elastic Store Slip. Set when the elastic store has either re-
peated or deleted a frame of data.