I'm relatively new to behaviors of serial ports such as RS-232, RS-422, and RS-485.
I'm wondering how do you initiate data transmission between a system and a device connected to each other by one of the 3 serial ports? Is this done thru software, or can be done thru commands inside a command line prompt, if so what's this command? How do we do this in Ubuntu and Windows OS?
For example, on a BACNet network, how does one initiate data transfer between 2 devices connected by serial cables