tapping into RS232

[SterlingY]

Odd project:

I have two devices that speak to each other via RS232. I don't know any of the settings, but I think I can guess, ar do a trial and error until I find the baud rate.

I want to build a device that splices into the wires that connects the two commumicating devices and reads the data that goes back and forth.

I am using a PIC 18F4550.

Is this possible? Any thoughts on how to do it or what problems I might face?

Cheers,

Sterling

[dhouston]

Google using "RS232 sniffer" and you'll find lots of links like...http://www.lammertbies.nl/comm/cable/RS-232-spy-monitor.html

[mister_e]

If at least a PC software run, YES you need a COM port sniffer on this PC, unless, Hyperterminal or MicroCode studio Serial Communicator will do the trick.

There's also protocol analyser software

There's also auto-baud detect EUSART PIC

I use HHD Software Serial Monitor... REALLY NICE, but not free...

[Dave]

SterlingY, You could (If you have a scope) look at the minimum width of a high period of the data signal and compute the baudrate. 1/minimum period = baudrate.

Dave Purola,
N8NTA

[ardhuru]

Hi,

Like Mister_e says, if either of the two devices is a PC, you could use a software-only solution.

I have been very impressed with http://www.serial-port-monitor.com/index.html

And this is *free*.

Hope you find it as useful as what I have.

Regards,

Anand