Epson 4500 - Manual (Page 187)

The Interface Boards
2. Reattach the board cover.
CAUTION: When
an optional interface board is installed, be
sure to disconnect the printer cable from the printer’s built-in
#8143 New Serial Interface
If you are using an optional interface, it may be necessary for you to
alter the communication protocol of the printer or the computer so that
they can communicate properly. In most cases, you should use the
information in your optional interface manual or your computer’s
manual to match the computer with the interface.
If you are using the #8143 optional interface board, make sure that you
read through the section below on baud rate selection. You may also
want to see the following sections on handshaking timing and error
handling for interface information specific to your printer.
For all other data transfer conventions, such as word structure or
communications protocol, use the information in the manual supplied
with your #8143 optional interface.
Using the Printer Options 5-49