
STANDARD PRODUCT
PM8315 TEMUX
DATASHEET
PMC-1981125
ISSUE 7
HIGH DENSITY T1/E1 FRAMER  WITH
INTEGRATED VT/TU MAPPER AND M13 MUX
PROPRIETARY AND CONFIDENTIAL
238
generated.  The generated pattern will be inserted in the output data stream, but
the phase of the pattern cannot be guaranteed.
For pattern detection, the PRGD will determine if a repetitive pattern of the length
specified in the pattern length register exists in the input stream.  It does so by
loading the first N bits from the data stream, and then monitoring to see if the
pattern loaded repeats itself error free for the subsequent 48 bit periods.  It will
repeat this process until it finds a repetitive pattern of length N, at which point it
begins counting errors (and possibly re-synchronizing) in the same way as for
pseudo-random sequences.  Note that the PRGD does NOT look for the pattern
loaded into the Pattern Insertion registers, but rather automatically detects any
repetitive pattern of the specified length.  The precise pattern detected can be
determined by initiating a PRGD update, setting PDR[1:0] = 00 in the PRGD
Control register, and reading the Pattern Detector registers (which will then
contain the 32 bits detected immediately prior to the strobe).
Common Test Patterns
The PRGD can be configured to monitor the standardized pseudo random and
repetitive patterns described in ITU-T O.151.  The register configurations
required to generate these patterns and others are indicated in Table 41 and
Table 42 below: