The pattern checker can be manually set to look for specific PRBS sequences and polarities or it can be set to automatically detect the incoming pattern and polarity. The PRBS checker supports the same set of PRBS patterns as the PRBS generator.

The pattern checker consists of an 11-bit error counter. The pattern checker uses 32-bit words, but every bit in the word is checked for error, so the error count represents the count of single bit errors.

To read out the bit and error counters, the pattern checker must first be frozen. Continuous operation with simultaneous read out of the bit and error counters is not supported in this implementation. Once the bit and error counter is read, they can be unfrozen to continue counting.