Epson DFX-5000 User Manual page 147

To use the data dump mode, follow these steps:
1. To enter the data dump mode, hold down the
LINE FEED
printer.
2. Next, run either an application program or one you have
written in any programming language. Your printer prints all
the codes sent to the printer in hexadecimal format as shown
below:
3. To turn off the data dump mode, press the
take the printer off line, and then turn off the printer. (The data
dump mode can also be cancelled by sending an INIT signal
from the computer.)
Look at the data dump shown in Step 2. By comparing the
characters printed in the right column with the printout of the
hexadecimal codes, you can check what codes are being sent to the
printer. If characters are printable, they appear as their true ASCII
characters. Nonprintable codes, such as control codes, are
represented by dots.
As an example of how to interpret a data dump printout, look at
the first five hex codes on the first line of the printout sample
(1B 40 1B 55 31). Each hex 1B represents the Escape code, 40
represents @, 55 represents U, 31 represents the numeral 1. Check
the first line of the right column and you will find a dot, an @
sign, another dot, a U, and a 1. If you look in the Command
Summary in Chapter 8, you will see that these are the commands
to initialize the printer and turn on unidirectional mode.
buttons at the same time while you turn on the
FORM FEED
ON LINE
button to
T r o u b l e s h o o t i n g 7 - 7
and