AT&T 6300 Service Manual page 235

DIAGNOSTICS
After giving the choice for the "PAUSE ON ERROR?" question,
the System Test displays the following menu listing all tests
available for the Video Option Board:
o -
RETURN TO MAIN MENU
1 - MEMORY TEST
2 - TRANSPARENT MODE
3 - TEXT WITH 400 LINE GRAPHICS
4 - TEXT WITH 200 LINE GRAPHICS
5 - 400 LINE GRAPHICS, 4 BIT PLANES, FULL LUT
6 - REDUCED LUT TEST (LITTLEBITl
10 - RUN ALL OF THE ABOVE TESTS
Specific tests can be run by entering the option number followed
by the ENTER key, or all tests may be run by entering the value
"10" followed by the ENTER key.
Note: Tests 3 and 4 must be run with the contrast control
set to approximately midrange. This is necessary in order
to distinguish between lines that are blinking from low
light to high light.
A detailed description with specific screens can be found in the
"MAINTENANCE" Section (Chapter 5). The following is a brief
description of the test performed by each of the MENU options.
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