American Megatrends MAN-759 manual Bootblock Code Checkpoint Codes, Code Description

Bootblock Code Checkpoint Codes

Code	Description
E0h	Verify the Boot Block BIOS checksum. Disable the
	internal cache, DMA, and interrupt controllers. Initialize
	the system timer. Start memory refresh.
E1h	Initialize the chipset registers. Set the BIOS size to 128K.
	Make the 512 KB base memory available.
E2h	Test the base 64 KB of system memory. Send the BAT
	command to the keyboard controller. Make sure that
	<Ctrl> <Home> was pressed. Verify the main system
	BIOS checksum.
E3h	The main system BIOS is good. Transfer control to the
	main system BIOS.
E4h	Start the memory test.
E5h	The memory test is over. Initialize the interrupt vector
	table.
E6h	Initialize the DMA and interrupt controllers.
E7h	Determine the CPU internal clock frequency.
E8h	Initialize the I/O chipset, if any.
E9h	Program the CPU clock-dependent chip set parameters.
EAh	Enable the timer and the floppy diskette interrupt. Enable
	the internal cache. Copy the boot block BIOS and pass
	control to the boot block BIOS in the 0000h segment.
EDh	Initialize the floppy drive.
EEh	Look for a diskette in drive A:. Read the first sector of the
	diskette.
EFh	Floppy read error.
F0h	Search for S759P.ROM in the root directory of the floppy
	diskette in drive A:.
F1h	The S759P.ROM file is not in the root directory.
F2h	Read the FAT table. Analyze the FAT to find the clusters
	occupied by the S759P.ROM.
F3h	Start reading the S759P.ROM file, cluster by cluster.
F4h	The S759P.ROM file is not the correct size.
F5h	Disable the internal cache. Raise the Vpp. Enable Flash
	write and reset the Flash ROM.
FBh	Detect the flash type.
FCh	Start erasing flash blocks.
FDh	Program the Flash ROM in the E0000-EFFFFh region.
FEh	Start programming Flash at F0000-FFFFF region.
FFh	Flash programming is successful. The computer reboots.

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