Checkpoint
No. Description
D4h Normal POST start
04h Programmable Interval T imer test in-progress or
failure
06h DMA page register write/read test in-prog r ess or
fail
08h RAM refresh verificat ion in-progress or failure
09h 1st 64K RAM test in-progress
0Ah 1st 64K RAM chip or data line failure - multi-bit
0Bh 1st 64K RAM odd/even logic failure
0Ch 1st 64K RAM address line failure
0Dh 1st 64K RAM parity test in-progress or failure
10h 1st 64K RAM chip or data line failure bit 0
20h Slave DMA register test in-progress or failure
21h Master DMA register test in-pro gress or failure
22h Master interrupt mask r egister test in-progress
or fail
23h Slave interrupt mask register test in-pr o gress or
fail
25h Interrupt vector lo ading in-progress
27h Keyboard controller test in-pro g r ess or failure
28h CMOS power -fail and checksum checks in-
progress
29h CMOS config info validation in-progress
2Bh Screen memory test in-progress or failure
2Ch Screen initialization in-progress or failure
2Dh Screen retrace tests in-progress or failure
2Eh Search for video ROM in-progress
30h Screen believed op erable
34h Timer tick interrupt test in-progress or failure
35h Shutdown test in-progr ess or failure
36h Gate A20 failure
37h Unexpected interrup t in protected mode
38h RAM test in-pr ogress or failure above address
0FFFFh
Error Messages A-3