Qmodem terminal

Hello,
I'm trying to communicate with an API315 indexer drive in order to set up the in/out pins which are configurable.
I've never used a terminal program, The only computer I have with a serial port that will fit the connector is running DOS only and I'm lost.
Would some kind person here help?
I've been able to install the program Qmodem as recommended in the manual, I've plugged it into the drive and fired up the software. It says I'm online but I'm unable to type anything into the terminal window.
I've also used the MODE command to configure COM1 as requested.
How can I check to see if the PC is transmitting over the cable or if the drive is responding.
At this point I have no idea where to start. Seems like something outa the 80's.
Also, if I go to split window, it lets me type commands but nothing happens when I push enter.
The program is made by Mustang Software but I can't find a site for them. All the links are dead.
Thanks for any help.
Brad

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