Supermicro SUPERSERVER 6010H, User Manual

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B-1
Appendix B: AMIBIOS POST Checkpoint Codes
Appendix B
AMIBIOS POST Checkpoint Codes
When AMIBIOS performs the Power On Self Test, it writes diagnostic codes
checkpoint codes to I/O port 0080h. If the computer cannot complete the boot
process, diagnostic equipment can be attached to the computer to read I/O port
0080h.
B-1 Uncompressed Initialization Codes
The uncompressed initialization checkpoint codes are listed in
order of execution:
Checkpoint Code Description
D0h The NMI is disabled. Power on delay is starting. Next, the
initialization code checksum will be verified.
D1h Initializing the DMA controller, performing the keyboard controller
BAT test, starting memory refresh, and entering 4 GB flat mode
next.
D3h Starting memory sizing next.
D4h Returning to real mode. Executing any OEM patches and setting
the Stack next.
D5h Passing control to the uncompressed code in shadow RAM at
E000:0000h. The initialization code is copied to segment 0 and
control will be transferred to segment 0.
D6h Control is in segment 0. Next, checking if <Ctrl> <Home> was
pressed and verifying the system BIOS checksum. If either <Ctrl>
<Home> was pressed or the system BIOS checksum is bad, next
will go to checkpoint code E0h.
Otherwise, going to checkpoint code D7h.