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SeaMAC: ssiEncodingNone vs ssiEncodingNrz

Aren’t the ssiEncodingNone and ssiEncodingNrz clock encoding methods in SeaMAC the same?

They are very similar, but the difference is that “None” tells the card not to attempt synchronizing the DPLL with the data. This means that the DPLL is effectively disabled in clockEncodingNone and as such it is not valid to select the DPLL as the RsetSource/TsetSource in this mode. This is done because the DPLL must run at a certain multiple of the desired data rate, depending on the mode, and this can restrict the maximum data rate compared to using a non-encoded clock. Therefore, the “None” option exists so applications using the RXC/TXC pins (instead of the DPLL/Clock Encoding) are not unnecessarily restricted by the DPLL clock.

More information on the SeaMAC Software.