Service manual

98 Self-Tests
B.13 MONO (test F)
The monochrome video display controller (MONO) power-up self-test has
one longword of status information in the following format:
MONO 0000.0XXX
where XXX is one of the status or error codes listed in the following table:
Code Status Definition
1 Status: Success
4 Error: Memory byte mask failure
8 Error: Memory error
10 Error: End-of-frame bit not in interrupt pending register
20 Error: End-of-frame failed to set for second time
40 Error: End-of-frame failed to set for third time
80 Error: No end-of-frame interrupt seen
100 Error: Wrong IPL level for EOF interrupt
200 Error: Interrupt request failed to clear interrupt pending register
bit
400 Error: End-of-frame interrupt not seen when looking at the
interrupt request register
800 Error: Error during cursor test
1000 Error: VDCSEL register read/write failure