AT&T PC 6300 - Keyboard Test

DIAGNOSTICS
Keyboard Teat
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Fixed Pattern Test: This test checks one memory block
at a time (16 KB) by writing to each memory location the
current test pattern and immediately verifying the pattern.
The test cycles through all of the memory 24 times, using a
different pattern each time. The 24 patterns in hexadecimal
format are: AAAA, FFFF, 0000, 5555, 0101, 0202, 0404, 0808,
1010, 2020, 4040, 8080, FEFE, FDFD, FBFB, F7F7, EFEF, -J
DFDF, BFBF, 7F7F, FFOO, OOFF, AA55, 55AA.
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The Keyboard internal hardware is first tested, and then a graphic
representation of the Keyboard layout is displayed. This layout is
used to manually test the individual keys. The LEDs on the ,
keyboard should blink while the keyboard hardware is being
tested. During this phase, the test is capable of detecting and
locating stuck keys. A stuck key is located by means of the scan
code displayed in the error messages (see error messages for
Keyboard test 400). The next phase of the test consists of
manually testing each key on the keyboard. The proper operation '
is indicated on the displayed keyboard layout. If any key does not M
function properly, you are asked to press ctrl and 0 (numeric key 'LJ
pad 0) and the error message is then displayed. If the test was
successful, you are asked to press ctrl and 1 (numeric key pad 1) ^
to proceed with other tests. j (,
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