Epson Apex 20020 - Manual (Page 178)

COLOR GRAPHICS ADAPTER AND CRT CHECK MENU
1 - Color graphics adapter check
2 - Attribute check
3 - Character set check
4
5
- 40-column character set check
- 320x200 graphics mode check
6 - 640x200 graphics mode check
7
8
- Screen paging check
- Light pen check
9 - Color video check
10 - Sync check
11 - Run all above checks
0 - Exit
Enter selection numb&:
If you specified to run the color adapter
check multiple times,
this menu does not appear and only the first test (Color
graphics adapter check) is performed.
If an error occurs during any of these tests, record the error
code and message, or print them out. Then contact your
Customer Care Center.
When you finish running the color adapter check,
press
0 and
Enter
to return to the DEVICE LIST.
Color Graphics Adapter Check
To check the color graphics adapter, press
1 and
then
Enter.
The computer checks the video RAM (display memory) on the
display adapter by writing test data to memory, and then
reading it back and comparing it to the written data. It also
tests the video enable signal of the display controller chip.