RELEASED
PM73123 AAL1GATOR-8
DATASHEET
PMC-2000097
ISSUE 2
8 LINK CES/DBCES AAL1 SAR
occurs. By not waiting for the second pointer mismatch in these situations where
bit integrity may have been lost, a quicker detection and recovery will result.
When a PTR_MISMATCH error occurs, the R_POINTER_REFRAMES counter is
incremented. Also, when a single pointer mismatch occurs, signaling information
will not be updated until a valid pointer is received to prevent corruption of the
signaling information.
Parity checking is also performed on pointers if R_CHK_PARITY is set in
R_MP_CONFIG. If a parity error is detected the PTR_PARITY_ERR sticky bit will
be set and the R_PTR_PAR_ERR counter will increment. If two consecutive
pointer parity errors occur, then the RALP forces an underrun condition and
resynchronizes. This resynchronization will cause R_POINTER_REFRAMES to
increment.
When any pointer error is detected an entry will be made into the
RCVN_STAT_FIFO, unless the corresponding enable bit is not set or this is not
the first enabled sticky bit to be set for this queue since the sticky bit register was
last cleared.
Figure 49 shows the state machine that checks for valid pointers and structures.
PMC-SIERRA, INC. PROPRIETARY AND CONFIDENTIAL
126
PMC [ PMC-SIERRA, INC ]
