> The most magic of all magic bytes is no byte at all. If you have the
ability
> to insert such bytes into the data stream then you presumably also have
the
> ability to pause transmission occasionally. If you pause for 1 word time
(10
> bits) (so that the circuit is at logical 1 / mark) then any properly
behaved
> UART that is monitoring the line will automatically drop into sync when
the
> character stream is restarted. This is the whole point of async
> communications. (Having a longer stop "bit" will also increase
> synchronization capability, but not as well as just stopping sending
> occasionally).
>
>         Russell McMahon
> .

This is absolutely correct. There is one small problem however.... it is
sometimes tricky to ensure a one-character-time idle on the link.

Also, my "magic-bytes" solution was intended to apply over an RF link where
a long idle time could confuse the data slicer. Note that such an issue
might also apply to an IR link.

If the data-slicer problem is not an issue, I am sure that there is a
shorter 'magic' sequence that would ensure byte alignment. This would allow
the transmitter to continue sending characters at all times, and not have to
pause.

Bob Ammerman
RAm Systems

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