Rainbow Electronics DS2154 - Manual (Page 26)

DS2154
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FASSA SSR.2 FAS Sync Active. Set while the synchronizer is searching for alignment at
the FAS level.
CASSA SSR.1 CAS MF Sync Active. Set while the synchronizer is searching for the CAS
MF alignment word.
CRC4SA SSR.0 CRC4 MF Sync Active. Set while the synchronizer is searching for the
CRC4 MF alignment word.
CRC4 SYNC COUNTER
The CRC4 Sync Counter increments each time the 8 ms
CRC4 multiframe search times out. The counter is
cleared when the DS2154 has successfully obtained
synchronization at the CRC4 level. The counter can
also be cleared by disabling the CRC4 mode
(CCR1.0=0). This counter is useful for determining the
amount of time the DS2154 has been searching for syn-
chronization at the CRC4 level. ITU G.706 suggests
that if synchronization at the CRC4 level cannot be
obtained within 400 ms, then the search should be
abandoned and proper action taken. The CRC4 Sync
Counter will rollover.
SR1: STATUS REGISTER 1 (Address=06 Hex)
(MSB) (LSB)
RSA1 RDMA RSA0 RSLIP RUA1 RRA RCL RLOS
SYMBOL POSITION NAME AND DESCRIPTION
RSA1 SR1.7 Receive Signaling All Ones / Signaling Change. Set when the contents
of timeslot 16 contains less than three zeros over 16 consecutive frames.
This alarm is not disabled in the CCS signaling mode. Both RSA1 and
RSA0 will be set if a change in signaling is detected.
RDMA SR1.6 Receive Distant MF Alarm. Set when bit–6 of timeslot 16 in frame 0 has
been set for two consecutive multiframes. This alarm is not disabled in the
CCS signaling mode.
RSA0 SR1.5 Receive Signaling All Zeros / Signaling Change. Set when over a full
MF, timeslot 16 contains all zeros. Both RSA1 and RSA0 will be set if a
change in signaling is detected.
RSLIP SR1.4 Receive Side Elastic Store Slip. Set when the elastic store has either re-
peated or deleted a frame of data.
RUA1 SR1.3 Receive Unframed All Ones. Set when an unframed all ones code is re-
ceived at RPOSI and RNEGI.
RRA SR1.2 Receive Remote Alarm. Set when a remote alarm is received at RPOSI
and RNEGI.
RCL SR1.1 Receive Carrier Loss. Set when 255 (or 2048 if CCR3.0=1) consecutive
zeros have been detected at RTIP and RRING. [Note: a test mode exists to
allow the DS2154 to detect carrier loss at RPOSI and RNEGI in place of
detection at RTIP and RRING].
RLOS SR1.0 Receive Loss of Sync. Set when the device is not synchronized to the
receive E1 stream.