Code
Cause
1-1-2
Microprocessor register failure
1-1-3
NVRAM read/write failure
1-1-4
ROM BIOS checksum failure
1-2-1
Programmable interval timer failure
1-2-2
DMA initialization failure
1-2-3
DMA page register read/write failure
1-3
Video Memory Test failure
1-3-1 through 2-4-4
Memory not being properly identified or used
1-3-2
Memory problem
3-1-1
Slave DMA register failure
3-1-2
Master DMA register failure
3-1-3
Master interrupt mask register failure
3-1-4
Slave interrupt mask register failure
3-2-2
Interrupt vector loading failure
3-2-4
Keyboard Controller Test failure
3-3-1
NVRAM power loss
3-3-2
Invalid NVRAM configuration
3-3-4
Video Memory Test failure
3-4-1
Screen initialization failure
3-4-2
Screen retrace failure
3-4-3
Search for video ROM failure
4-2-1
No timer tick
4-2-2
Shutdown failure
4-2-3
Gate A20 failure
4-2-4
Unexpected interrupt in protected mode
4-3-1
Memory failure above address 0FFFFh
4-3-3
Timer-chip counter 2 failure
4-3-4
Time-of-day clock stopped
4-4-1
Serial or parallel port test failure
4-4-2
Failure to decompress code to shadowed memory
4-4-3
Math-coprocessor test failure
4-4-4
Cache test failure
Quick Reference Guide
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