I have been using Tom McGahee's RS-232 code to get started on an RS-232
project. I've stripped the code down so that it's "receive only," which is
what I'll be needing.

The problem that I am having is that the MSB of the receive buffer seems to
invert if I type the same character twice. That is, I can type characters
all day long, but if I type "11111111," the MSB inverts each time I type
"1," after the second one is typed. This happens with any character sent,
including 0xFF, which obviously has the MSB set. Typing any character
in-between repeats prevents this problem, and I see no problems when typing
non-repeating characters.

I can't seem to find any reason for this, and my code needs to be able to
receive 0xFF twice in a row and tell it apart from 0xFF followed by 0xEF, so
I can't just ignore the MSB, as you could if you were just doing ASCII text.

Has anyone seen this behavior before and is there a way around it? Do I need
to clear some buffer or something? I tried cycling RCSTA,CREN between each
character and it still does it.

Thanks,
    Ian Jordan

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