B-1
Appendix B: BIOS POST Checkpoint Codes
Appendix B
BIOS POST Checkpoint Codes
When AMIBIOS performs the Power On Self Test, it writes checkpoint codes to I/O
port 0080h. If the computer cannot complete the boot process, diagnostic equip-
ment 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 check-
sum will be verifi ed.
D1h
Initializing the DMA controller, performing the keyboard controller BAT test, starting
memory refresh and entering 4 GB fl at 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.
Summary of Contents for AS2041M-32R Plus
Page 1: ...AS2041M 32R AS2041M T2R USER S MANUAL 1 0 SUPER ...
Page 5: ...v Preface Notes ...
Page 16: ...1 6 AS2041M 32R 2041M T2R User s Manual Notes ...
Page 25: ...Chapter 2 Server Installation 2 9 Figure 2 4 Accessing the Inside of the System ...
Page 30: ...3 4 AS2041M 32R 2041M T2R User s Manual Notes ...
Page 67: ...Chapter 6 Advanced Chassis Setup 6 5 Figure 6 3 Installing the Air Shroud ...
Page 73: ...Chapter 6 Advanced Chassis Setup 6 11 Figure 6 6 Removing Replacing the Power Supply ...
Page 74: ...6 12 AS2041M 32R 2041M T2R User s Manual Notes ...
Page 94: ...A 2 H8QM3 2 H8QMi 2 User s Manual Notes ...
Page 102: ...B 8 AS2041M 32R 2041M T2R User s Manual Notes ...
Page 106: ...C 4 AS2041M 32R 2041M T2R User s Manual Notes ...