6.7.4.2.3.4 Train-SNW defines two training patterns: TRAIN pattern and TRAIN)DONE pattern. Both are defined as their respective redundant primitive followed by 58 dwords set to 0x00000000 scrambled and 8b10b encoded. Furthermore, the scrambler is initialized at the end of RCDT and is not re-initialized after that.

The question we have is : Does the scrambler pause while sending TRAIN or TRAIN_DONE primitives; that is, is the dword following the primitive the scrambler’s successor dword to the dword preceding the primitive? Or does the scrambler run continuously, and TRAIN or TRAIN_DONE is overlayed on top of scrambler dwords? I would expect the former, but I don’t feel that the current draft (sas2r10) is clear in this regard.

Thanks,

Robert Watson

PMC-Sierra, Inc.