Thanks Henrik.

Lets see if I understand-

If I am receiving 16 byte packets, To get them in order, I need to:

Read first byte
Throw it away
read next 16 bytes.

but to get the last byte, do I need to an extra read to get the last from FIFO to RCREG?

Because I don't want the last byte as the next packet first byte.

Logic is Walter's (scalerobotics) fault. He turned me on to it. Best diagnostic tool yet for this stuff. Don't leave home without it