In the terminal.bas program there are these three lines
'Open communications port 2. It's handle is #comm.
'If you need to change to com 1, this is the line to modify
open "COM1:9600,n,8,1,ds0" for random as #comm
I think that all you would do is change COM1 to COM2 or COM3 depeding on the port you are looking for, but I am just taking a wild guess.