Epson EL 3S/33 - Manual (Page 94)

Also, see the documentation that came with the option card to
set any necessary DIP switches or jumpers on the card.
The main system board of your computer may also have some
jumpers that must be set for the option card to work properly.
See Chapter 3 for system jumper information.
Your system may need to operate at the slower processor speed
to access the device. Try reducing the processor speed (see
Chapter 2) or inserting a wait state through the SETUP
program (see Chapter 1).
You may have inserted an older option card that works at
-5 volts. Make sure you install option cards that meet the
system’s power requirements.
An external device connected to the option card is not
working correctly.
Make sure you are using the proper cable to connect the device
to the card.
Memory Module Problems
The memory count displayed by the power-on diagnostics
program is incorrect.
You may have installed the SIMMs incorrectly. They may be
the wrong type or speed, or they may not be inserted all the
way. See Chapter 3 for information on installing SIMMs.
6-10 Troubleshooting