I'm having problems trying to use DTR/DSR communication mode on the serial-port, I want to use for printing (POS-printer, STAR 2000). It just won't work, although I perform all the steps exactly as it is said in the user's manual for the printer, i.e. the cable is made OK, and printer's jumpers are set accordingly.

I was able to find a cable combination, that works though, but it still doesn't work with some motherboards (it works now with some from ASUS and some from Gigabyte, and it won't work at all with any A-bit motherboard).

I tried to change drivers for serial ports: com.sys, qcom.sys, SIO all result in the same thing.

Does anybody know if there is anything special about using DTR/DSR communication in OS/2?