I like the idea of using a preamble to 'train' the receiving algorithm.  
I could use that to lock the timing and the data length to release it again.
- Thus my packets would be:  Preamble/SFD, Data, CRC.  The overhead may 
be longer than my data :)  I may not need and SFD if my preamble is 
robust enough.

  Thanks,
Phil

Scott Dattalo wrote:

> <SNIP>
>
>If you decide to use Manchester encoding, then I'd suggest structuring
>your data streams with a preamble that can a) allow your receiver's AGC
>circuit to settle and b) generate a pulse that can be used to
>synchronize the incoming data. For example, in one application I
>generate a preamble that consists of a high pulse that lasts 4 bit
>times, followed by a low one that is also 4-bit times. This is then
>followed by a 32-bit hamming protected, Manchester encoded data burst.
>(Sorry - I can't share the code).
>
>Scott
>
>  
>



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