[ILUG] Reverse engineering serial protocol

[Cian Cullinan]

<snip>
> The first thing I need to do is verify the baud rate. I suspect that it
> is 9600 8N1, but have no way of being sure. Does anyone know of a way to
> verify the baud-rate/data/parity/stop-bits for an RS232 interface that
> doesn't require an oscilloscope?
> 
> I've tried listening with minicom, and wrote a program to read bytes
> from /dev/ttyS0 and print them to the screen in the hope of something
> readily apparent, but no joy so far. My next step is to connect an RS232
> cable from my linux box to my windows laptop that has the drivers
> installed, sned it some characters, and see what the mouse pointer does.
<snip>

I know you say you've tried minicom, but have you tried all the baud
rate/stop-start-bit combinations? By varying these you should be able
to find out the serial parameters that the screen is using. The screen
won't necessarily be outputting regular  ol' ASCII though. I don't
know if minicom is cable of displaying output in hex, but according to
google GTKTerm (a hyperterm clone) is.
Cian