Uncompressed Initialization Codes | SUPER MICRO Computer H8DI3+

Appendix B: BIOS POST Checkpoint Codes

B-3 Uncompressed Initialization Codes

The following runtime checkpoint codes are listed in order of execution. These codes are uncompressed in F0000h shadow RAM.

Checkpoint	Code Description

03h	The NMI is disabled. Next, checking for a soft reset or a power on condition.

05h	The BIOS stack has been built. Next, disabling cache memory.

06h	Uncompressing the POST code next.

07h	Next, initializing the CPU and the CPU data area.

08h	The CMOS checksum calculation is done next.

0Ah	The CMOS checksum calculation is done. Initializing the CMOS status register for date and
	time next.

0Bh	The CMOS status register is initialized. Next, performing any required initialization before the
	keyboard BAT command is issued.

0Ch	The keyboard controller input buffer is free. Next, issuing the BAT command to the keyboard
	controller.

0Eh	The keyboard controller BAT command result has been veriﬁed. Next, performing any
	necessary initialization after the keyboard controller BAT command test.

0Fh	The initialization after the keyboard controller BAT command test is done. The keyboard
	command byte is written next.

10h	The keyboard controller command byte is written. Next, issuing the Pin 23 and 24 blocking and
	unblocking command.

11h	Next, checking if <End or <Ins> keys were pressed during power on. Initializing CMOS RAM
	if the Initialize CMOS RAM in every boot AMIBIOS POST option was set in AMIBCP or the
	<End> key was pressed.

12h	Next, disabling DMA controllers 1 and 2 and interrupt controllers 1 and 2.

13h	The video display has been disabled. Port B has been initialized. Next, initializing the chipset.

14h	The 8254 timer test will begin next.

19h	Next, programming the ﬂash ROM.

1Ah	The memory refresh line is toggling. Checking the 15 second on/off time next.

2Bh	Passing control to the video ROM to perform any required conﬁguration before the video ROM
	test.

2Ch	All necessary processing before passing control to the video ROM is done. Looking for the
	video ROM next and passing control to it.

2Dh	The video ROM has returned control to BIOS POST. Performing any required processing after
	the video ROM had control

23h	Reading the 8042 input port and disabling the MEGAKEY Green PC feature next. Making the
	BIOS code segment writable and performing any necessary conﬁguration before initializing the
	interrupt vectors.

24h	The conﬁguration required before interrupt vector initialization has completed. Interrupt vector
	initialization is about to begin.

25h	Interrupt vector initialization is done. Clearing the password if the POST DIAG switch is on.

27h	Any initialization before setting video mode will be done next.

28h	Initialization before setting the video mode is complete. Conﬁguring the monochrome mode and
	color mode settings next.

2Ah	Bus initialization system, static, output devices will be done next, if present. See the last page
	for additional information.

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