![](http://datasheet.mmic.net.cn/330000/PM5381_datasheet_16444347/PM5381_142.png)
PRELIMINARY
PMC-Sierra, Inc.
PM5381 S/UNI-2488
DATASHEET
PMC-2000489
ISSUE 1
SATURN USER NETWORK INTERFACE FOR 2488 MBIT/S
Proprietary and Confidentail to PMC-Sierra Inc., and for its Customer’s Internal Use
121
FIFO_UNDF_I:
The FIFO Underflow bit provides a status indication of an underflow condition in the Rx data
slip-buffer. When FIFO_UNDF_I is set to ‘1’ the data written to the slip-buffer has underflowed
and data invalid data has been read from the FIFO. This bit is only cleared by over-writing
with a ‘1’.
FIFO_OVRF_I:
The FIFO Overflow bit provides a status indication of an overflow condition in the Rx data
slip-buffer. When FIFO_OVRF_I is set to ‘1’ the data written to the slip-buffer has overflowed
and data has been lost. This bit is only cleared by over-writing with a ‘1’.
PRBS_ERR_I:
The PRBS Bit Error bit provides a status indication that a bit error has been detected in the
comparison between the incoming data and the locally generated data. The PRBS_ERR_I is
set high when the monitor is in the synchronized state and when an error in a PRBS byte is
detected. This bit is only cleared by over-writing with a ‘1’.
PRBS_SYNC_I:
The PRBS Synchronization bit indicates that a change in the status of PRBS Monitor has
occurred. the comparison between the incoming data and the PRBS pattern generated
locally. The PRBS_SYNC_I is set high when the monitor is in the synchronized state and has
received four consecutive errored bytes forcing the PRBS monitor to resynchronize. This bit
is only cleared by over-writing with a ‘1’.