
PM5317 SPECTRA-9953 Telecom Standard Product Data Sheet
Release
Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC-2000741, Issue 5
491
3. Read the BUSY bit. If it is equal to logic 0, continue to 4. Otherwise, continue polling the
BUSY bit.
4. Read the indirect data registers to find the state of the register bits for the selected channel
number.
17.6 Using the Performance Monitoring Features
The performance monitor counters within the different blocks are provided for performance
monitoring purposes. All performance monitor counters have been sized to not saturate if
polled every second. The counters will saturate and not roll over if they reach their maximum
value.
Writing can do a device update of all the counters to the SPECTRA-9953 Master Input Signal
Activity, Accumulation Trigger register (002H). If this register is written to, the TIP bit in the
SPECTRA-9953 Master Accumulation Transfer and Parity Error Interrupt Status register can be
polled to determine when all the counter values have been transferred and are ready to be read.
17.7 Using The Section/Line Bit Error Rate Monitoring Features
The Bit Error Rate Monitor (SBER) block counts and monitors line BIP errors over
programmable periods of time (window size). It can monitor to declare an alarm or to clear it if
the alarm is already set. A different threshold must be used to declare or clear the alarm, whether
or not those two operations are performed at the same BER. The following tables list the
recommended content of the SBER registers for different speeds (STS-N) and error rates
(BER). Both SBERs in the TSB are equivalent and are programmed similarly. In a normal
application, they will be set to monitor different BER.
When the SF/SD CMODE bit is 1, this indicates that the clearing monitoring is recommended to
be performed using a window size that is eight times longer than the declaration window size.
When the SF/SD CMODE bit is 0 this indicates that the clearing monitoring is recommended to
be performed using a window size equal to the declaration window size. In all cases the clearing
threshold is calculated for a BER that is 10 times lower than the declaration BER, as required in
the references. The tables indicate the declare BER, the evaluation period and the recommended
CMODE and associated thresholds.
The saturation threshold is not listed in the table. It is programmed with the value 0xFFFFFF by
default, deactivating saturation. Saturation capabilities are provided to allow the user to address
issues associated with error bursts. It enables the user to determine a ceiling value at which the
error counters will saturate, letting error bursts pass through within a frame or sub window
period.
Since the monitoring algorithm is based on a pseudo-sliding window containing eight sub
intervals, the time required to declare or clear an alarm can take up to nine sub-accumulation
periods (SAP). The following tables thus consider that each SAP must take a value lower or
equal to 1/9
th
of the timing constraint, in frames.