How do I configure and communicate with a serial port? [closed]

Answer 1

Depending on the device You are trying to communicate with, there may be more parameters than the baud rate, number of data bits, type of parity checking and number of stop bits to consider. If I recall correctly, modems use nine lines of the RS-232C interface. Some devices like, for example cash registers, may use hardware handshaking on RTS/CTS lines or on DTR/STR lines.

In general it's good to know how the interface works. You can't communicate if the baud rate doesn't match, but wrong setting of other parameters might kind of work. For example You can easily send data to the device expecting 1 stop bit with 2 stop bits set. Problems start when You try to receive data in such case. You can also use appropriately set parity bit as one of stop bits, etc.

Answer 2

For C/C++ on Windows you have (at least) two choices:

1. Use the SerialPort class provided by .NET.
2. Use the Win32 API. There is an extensive MSDN article dating back to 1995, and many free libraries and examples on the web to get you started.

The .NET option will be much easier.

Answer 3

From the other side, if you want to do it using C#, which will run on both Windows and Linux--with some limitations (EDIT: which may be out of date. I have no way to test it.). Just create a SerialPort object, set its baudrate, port and any other odd settings, call open on it, and write out your byte[]s. After all the setup, the SerialPort object acts very similar to any networked stream, so it should be easy enough to figure out.

And as ibrandy states, you need to know all these settings, like baud rate, before you even start attempting to communicate to any serial device.

Answer 4

At work we use teraterm and realterm for checking serial data is correctly formatted. Also we have a hardware splitter with a switch so we can monitor traffic to our application via a cable back to another port.

Windows allows you access to the serial port via CreateFile. That gives you a handle and from there you can configure access.