East meets West: Doom II multiplayer via null modem cable

[YetAnotherJPCUser]

You can play multiplayer in Doom II via null modem cable. Doom II (PC98) can connect to an IBM PC compatible computer. In my case it's a Toshiba Tecra. I've played multiple levels without any interference. Just make sure that the baudrate on both systems is identical.

On the PC98 I have installed Doom II CD-ROM edition.
Default baudrate is 9600. Change baudrate via Doom's setup.exe

On the Toshiba I have installed Doom II from the id anthology collection (1996).
Default baudrate is 14000. Change baudrate via Doom's sersetup.exe -com1 -9600