My work involves interacting with legacy hardware that uses serial ports. I often have to monitor more than one serial line, and for the purpose I have a couple of the common USB serial adaptors. When I connect both of them to the same (Windows 10) machine, irregularities show up. Both ports show up in device manager, but only the first one that I plug in to the USB connector works. The other one indicates port not open when I try to send data via RealTerm.
I have also seen the situation where when I plug the second adaptor in, its port comes up, but the one for the other adaptor disappears. Does anyone know a way that two devices can happily coexist on the one machine? Thanks in advance.
Just ion case this helps anyone in the future......
The problem seems to be caused by the fact that one of the adaptors was coming in via a (powered) USB hub. When I liberated another native port on the machine so I could host both serial adaptors directly, everything worked fine.
Not worth hunting the cause down, a solution is at hand.