Connecting devices with the RS232 port

Has anyone realized a driver for device XXX? There are many secondhand XXX´s around Second Hand. It has a RS232 plug.

If your device has a RS232 plug, and there is some documentation, it is most likely that you can patch a driver for it within vvvv.

For some basics about the RS232 protocol, check the following articles:

• Wikipedia Article about RS232
• More about RS232 connectors

Reverse engineering protocols with vvvv

Even if there is no documentation it is quite possible to reverse engineer serial protocols by using a second computer with two serial ports:

• Have one computer using your device with the regular drivers or application software.
• Check the current serial port settings in the device manager for baud rate, parity etc. of the used rs232 port.
• Setup a second computer with vvvv and create two RS232 nodes so that all data from com1 goes to com2 and vice versa. enter the baud rate, parity information in both of the rs232 nodes.
• Connect both computers with a crossed rs232 cable (null modem cable), and plug your device into the second computer.
• Now everything should be working in the same fashion as before, and you can start training your inductive skills by analyzing what kind of data gets transferred and why.

You now may either opt to emulate your driver or your device. the first is what you asked for, the latter may be fun as well.

There are also sophisticated programs available which allow you to intercept all data flowing between your device and an application, so you can avoid setting up a second computer. i remember being happy with the SerMon program from HHD Software.http://www.hhdsoftware.com/sermon.html Note there is a free trial version.

How can i verify that my serial port works?

you may shorten Pins 2 and 3 of your 9-pole D-Sub connector.
any string you send using RS232 (Devices) should be answered now to its output.

Links

Microsoft also provides a free tool from Sysinternals:http://www.microsoft.com/technet/sysinternals/utilities/portmon.mspx