Agilent Technologies 54835A, 45A, 46A manual POST Code Listing AMI Motherboard only, Troubleshooting

Chapter 5: Troubleshooting

POST Code Listing (AMI Motherboard only)

POST Code Listing (AMI Motherboard only)

Use the following listing to troubleshoot the motherboard. You will need a POST (Power-On Self Test) card installed in an ISA slot to use this listing.

POST Code Listing

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.
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 Home was pressed and verifying the BIOS checksum. If
	either Home was pressed or the system BIOS checksum is bad, next will go to checkpoint code
	E0h. Otherwise, going to checkpoint code D7h.

Bootblock Recovery Codes

The bootblock recovery checkpoint codes are listed in order of execution:

Code	Description
E0h	The onboard floppy controller, if available, is initialized. Next, beginning the base 512 KB memory
	test.
E1h	Initializing the interrupt vector table next.
E2h	Initializing the DMA and Interrupt controllers next.
E6h	Enabling the floppy drive controller and Timer IRQs. Enabling internal cache memory.
EDh	Initializing the floppy drive.
EEh	Looking for a floppy diskette in drive A:. Reading the first sector of the diskette.
EFh	A read error occurred while reading the floppy disk in drive A:.
E0h	Next, searching for the AMIBOOT.ROM file in the root directory.
F1h	The AMIBOOT.ROM file is not in the root directory.
F2h	Next, reading and analyzing the floppy diskette FAT to find the clusters occupied by the
	AMIBOOT.ROM file.
F3h	Next, reading the AMIBOOT.ROM file, cluster by cluster.
F4h	The AMIBOOT.ROM file is not the correct size.
F5h	Next, disabling internal cache memory.
FBh	Next, detecting the type of flash ROM.
FCh	Next, erasing the flash ROM.
FDh	Next, programming the flash ROM.
FFh	Flash ROM programming was successful. Next, restarting the system BIOS.

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