Shawn Wilton wrote:
> I'm having issues communicating with an XP PC over RS232.
>
> I know my code is good because I can communicate via serial using one of
> those USB-UART chips.  But when I hook this PICDEM+ to the PC via a genuine
> RS232 serial port, I constantly get an overrun error.  I looked at the data
> in the debugger and I'm getting "."(0xC3) constantly.  Apparently faster
> than the uC can handle the packets.
>
> Any ideas where the data is coming from?  There's nothing running on that
> serial port in terms of s/w.  Perhaps someone else has seen this or has an
> idea what's going on?
>
>   
It sounds like you are not grounding the serial from the PC.

I would hookup Hyperterminal and try it: set the flow control to 
XON/XOFF (just don't send an XOFF).
Lets see what you get from the PIC. If the data is garbled, or if 
hyperterminal isn't sending anything, and you
are STILL receiving something, you have a ground fault.


--Bob
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