Does the CC110x radio perform bit synchronization before or after its Manchester decoding logic?
I am working with a receiver application where the data will be Manchester encoded but the packet format does not contain any form of '10101010..." preamble pattern in the raw (un-encoded) data. The packet format does specify sync bytes, so I have set up the CC110x to use packet processing with PQT=0 (since there will be no preamble pattern).
I see that with this set up, the radio packing processing does not detect a good percentage of the packets that are sent to it. However, when I manually add the preamble pattern (not a valid real-world condition), I receive 100% of the packets.
A curious note is that the sync word pattern in the packet format being use provides a 10101010 sequence as its first byte, but only when it is Manchester encoded. If I disable the Manchester coding in the radio hardware and decode the Manchester manually, the percentage of packets received correctly increases dramatically, even with only a single "preamble" byte pattern. This leads me to believe that the bit synchronization in the radio rx circuitry is performed after decoding. Can anyone confirm?
