Verify that the parallel or serial card is properly seated:
a.
Turn the power off and open the machine.
b.
Remove and reseat the card in the bus.
Run the Hardware/Kernel Manager to configure the
serial port and parallel port drivers
and verify that the port is listed in your kernel configuration.
See
``Configuring drivers with the Hardware/Kernel Manager'' in the SCO OpenServer Handbook.
Verify that the card itself is correctly configured.
Check the documentation provided with the card.
If possible, try setting the card for a different configuration.