Semiconductor Group
299
09.98
PEB 22554
Operational Description T1 / J1
synchronization might have been based on an alias framing
pattern, setting of FMR0.FRS will lead to synchronization on
the next candidate available. However, only the previously
assumed candidate will be discarded in the internal framing
pattern memory. The latter procedure can be repeated until the
framer has locked on the right pattern (no extensive CRC
errors). Therefor bit FMR1.CRC must be set.
11… F24:
Synchronization is achieved on verification the framing pattern
and
the CRC6 bits. Synchronous state is reached when
framing pattern and CRC6 checksum are correctly found. For
correct operation the CRC check must be enabled by setting bit
FMR1.CRC6.
DAIS…
Disable AIS to System Interface
0…
AIS is automatically inserted into the data stream to RDO if
QuadFALC is in asynchronous state.
1…
Automatic AIS insertion is disabled. Furthermore, AIS insertion
can be initiated by programming bit FMR2.SAIS.
SAIS…
Send AIS Towards System Interface
Sends AIS (blue alarm) via output RDO towards system interface.
This function is not influenced by bit FMR2.DAIS.
PLB…
Payload Loop Back
0
…
Normal operation. Payload loop is disabled.
1…
The payload loopback will loop the data stream from the
receiver section back to transmitter section. Looped data is
output on pin RDO. Data received at port XDI, XSIG, SYPX and
XMFS will be ignored. With FMR4.TM=1 all 193 bits per frame
will be looped back. If FMR4.TM=0 the DL- or FS- or CRC- bits
will be generated internally. AIS is sent immediately on port
RDO by setting the FMR2.SAIS bit. During payload loop is
active the receive time-slot offset (registers RC1/0) should not
be changed. A write access to register XC1 will set the
read/write pointer of the transmit elastic buffer into its optimal
position to ensure a maximum wander compensation.
AXRA…
Automatic Transmit Remote Alarm
0
…
Normal operation
1…
The Remote Alarm (yellow alarm) bit will be automatically set in
the outgoing data stream if the receiver is in asynchronous