Dave,
thanks for the usbcom.sys tip. That got me started, at least. I added the following two lines to my CONFIG.SYS
DEVICE=C:\OS2\BOOT\USBCOM.SYS /V /N:2
DEVICE=C:\OS2\BOOT\USBCOM.SYS /V /N:3
and the messages on boot up appear to say the driver is loaded for each com port.
But when I enter MODE COM2 or MODE COM3 I get the message
The system cannot find the device specified.
I have one physical COM port in the motherboard, which is used normally used
by my ACECAD driver. The CONFIG.SYS lines for that driver are
DEVICE=C:\OS2\ACECAD.SYS
DEVICE=C:\OS2\MDOS\VMOUSE.SYS
DEVICE=C:\OS2\BOOT\POINTDD.SYS
DEVICE=C:\OS2\BOOT\AMOUSE.SYS STYPE=ACECAD$
DEVICE=C:\OS2\BOOT\USBMOUSE.SYS
If I put COM.SYS in my config.sys with the ACECAD driver I get an error message when it tries to load COM.SYS.
If I take out the ACECAD stuff out of CONFIG.SYS COM.SYS loads and I can use COM1 - and MODE COM1 works correctly.
Martin,
The device is an IBM 6094-20 Lighted Program Function Keyboard (LPFK) which needs a serial connection.
You can see it in action, along with a 6094-10 Dials device at
https://www.reddit.com/r/retrobattlestations/comments/g6qfd7/ibm_6094_dials_lpfk_lighted_programmable_function/I ported the source for a a Linux "driver" (actually just an interface to the serial port for this device with a test program) to OS/2 - but to do that I had to remove the ACECAD driver and connect the LPFK to the real serial port on my machine. I am now trying to get it to work through a USB - > serial adapter.