[Trlog] USB -> serial adapters for DOS?

[John Unger]

I think this question has come up before but don't remember is anyone has 
found a solution:

I am trying to configure a laptop with only one serial port for SO2R, so 
need to figure out how to add another serial port somehow. The simplest 
approach would be to use one of the USB to serial adapters that are out 
there, but I don't know if any of them have DOS drivers.

Has anyone had any success with getting around this situation?

tnx es 73 - John, W4AU