Epson Apex 20020 - Manual (Page 176)

Character Set Check
To check your character
set,
press
3
and then
Enter.
The
characters that are included in the internal character generator
are displayed. Check the characters displayed on your screen
against this illustration:
After checking the characters, respond to the prompt:
Is the display correct (Y/N)?
If the characters displayed match the illustration, press Y and
Enter.
If they do not match the illustration, press
N
and then
Enter
to display the error message.
Video Check
To check the video output of your monochrome adapter, press
4 followed by
Enter.
This check displays two different screens,
black and intensified white. First you see the black screen; press
any key to display the intensified white screen. Then press any
key to end this check.