Hello!
some of You certainly got a lot of experience on this, so why not ask for Y=
our
opinion and suggestion. :)

I need to implement absolutely reliable communication over a serial link (U=
ART).

My needs are:

# I would like to send and receive packets of arbitrary length.

# The counterpart may be a PC with preemptive multitasking thus no timeouts=
 or
such can be exploited to define packet start and packet end.

# No excessive bandwidth waste for the protocol.

# Hardware/eletromagnetic interference may happen and must not corrupt the =
data
(i.e. if not error correction, at least error detection is needed).

# The system must not lock or crash in the above case, report the error and=
 get
ready for the next packet.

# Finally, the UART must be setup as 8 bits length.

After a lot of mumble-mumbling, the definition of weird protocols and so on=
,
I rediscovered an ancient, existing, protocol:
SOH, data (eventually DLE), EOT, and finally CRC

It works although it has the defect that it will double the bandwidth requi=
red if
you send certain bytes.

Has anybody a better solution to suggest? :)

Thanks a lot!

Cheers,
Mario

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