"William "Chops" Westfield wrote:
>>> 'm still confused over why I don't get
>>> garbage after a power-on reset. The chip spits out garbage only after
>>> executing the reset instruction.
>
> If an UART is receiving data continuously, and the sender "glitches"
> in the middle of a character but begins transmitting continuously
> again, they can remain "out of sync" indefinitely, and the receiver
> sees garbage.  Async needs a period of a bit more than 1 character
> time in the Mark (idle) state to get things synchronized again.
>
> (You didn't say whether the line was continually transmitting, but
> I've seen this happen before.  Usually on some sort of data line that
> has continuous data, when the receiver reboots and initializes its
> uart in the middle of the stream.)

Olin, Bill: thank you for your insight, it suggested another way to find out 
what's going on.

The line is not transmitting continuously, but it does echo back characters 
that it receives on RS232. So it's conceivable that the last character 
echoed (<CR>) is still being transmitted, when the PIC resets, and sends the 
welcome string. A circuimstancial piece of evidence in support of the theory 
is that I do recall the number of characters in the "garbage" string being 
roughly the same as in the real string.

Olin's suggestion would be the proper way to handle the problem, but a 
quick-and-dirty way to conclusively prove the above theory, would be to 
insert a delay before the reset instruction (this would give the UART enough 
time to finish transmitting the echo).

I will report back tomorrow (hopefully). Thanks again!

Vitaliy 

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