Epson Apex 20020 - Manual (Page 128)

When you finish changing the jumpers, carefully replace the
memory card in its slot and secure it with the retaining screw.
Multi-function Card Jumpers
The jumpers on the multi-function card control the parallel
port address and the serial port address. You normally address
the parallel and serial ports in the computer as the primary
ports (LPT1 and COM1). However, if you install an additional
parallel or serial port and want it to be the primary port, you
need to change the jumpers on the multi-function card so the
built-in port becomes secondary (LPT2 and COM2).
The following table shows the jumpers on the multi-function
card that control the parallel port.