DS2154 Dallas Semiconducotr, DS2154 Datasheet - Page 35

• Manufacturer Part Number: DS2154
• Description: Enhanced E1 Single Chip Transceiver
• Manufacturer: Dallas Semiconducotr

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 synchronization 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)
RSA1
SYMBOL
RDMA
RSLIP
RUA1
RLOS
RSA1
RSA0
RRA
RCL
RDMA
POSITION
SR1.7
SR1.6
SR1.5
SR1.4
SR1.3
SR1.2
SR1.1
SR1.0
RSA0
NAME AND DESCRIPTION
Receive Signaling All 1s / Signaling Change. Set when the
contents of timeslot 16 contains less than three 0s 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.
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.
Receive Signaling All 0s / Signaling Change. Set when over a
full MF, timeslot 16 contains all 0s. Both RSA1 and RSA0 will
be set if a change in signaling is detected.
Receive Side Elastic Store Slip. Set when the elastic store has
either repeated or deleted a frame of data.
Receive Unframed All 1s. Set when an unframed all 1s code is
received at RPOSI and RNEGI.
Receive Remote Alarm. Set when a remote alarm is received at
RPOSI and RNEGI.
Receive Carrier Loss. Set when 255 (or 2048 if CCR3.0=1)
consecutive 0s 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].
Receive Loss of Sync. Set when the device is not synchronized
to the receive E1 stream.
RSLIP
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RUA1
RRA
RCL
RLOS
(LSB)
DS2154