Is it possible to mount a machine to test the parallel cable without using the printer?

You can test RS232 cable with a multimeter by wire.

Pinout:

When a serial printer is connected to a PC, the handshaking is not symmetrical any more. In that case a cable is used where some handshaking lines at the PC side are looped back. On the printer side only the data lines and one handshaking line are used.

How to test the port itself - http://stadi.hu/sw/lptdebug_en.html

Разговор глухого со слепым. Один спросил про параллельный порт, другой прочитал и зачем-то написал про последовательный...