Amibios Post Code, Checkpoint Description

4.3 AMIBIOS Post Code

The POST code checkpoints are the largest set of checkpoints during the BIOS pre- boot process. The following table describes the type of checkpoints that may occur during the POST portion of the BIOS:

Checkpoint	Description
03	Disable NMI, Parity, video for EGA, and DMA controllers. Initialize
	BIOS, POST, Runtime data area. Also initialize BIOS modules on
	POST entry and GPNV area. Initialized CMOS as mentioned in the
	Kernel Variable "wCMOSFlags."
04	Check CMOS diagnostic byte to determine if battery power is OK and
	CMOS checksum is OK. Verify CMOS checksum manually by
	reading storage area. If the CMOS checksum is bad, update CMOS
	with power-on default values and clear passwords. Initialize status
	register A.
	Initializes data variables that are based on CMOS setup questions.
	Initializes both the 8259 compatible PICs in the system
05	Initializes the interrupt controlling hardware (generally PIC) and
	interrupt vector table.
06	Do R/W test to CH-2 count reg. Initialize CH-0 as system timer.Install
	the POSTINT1Ch handler. Enable IRQ-0 in PIC for system timer
	interrupt.
	Traps INT1Ch vector to "POSTINT1ChHandlerBlock."
08	Initializes the CPU. The BAT test is being done on KBC. Program
	the keyboard controller command byte is being done after Auto
	detection of KB/MS using AMI KB-5.
0A	Initializes the 8042 compatible Key Board Controller.
0B	Detects the presence of PS/2 mouse.
0C	Detects the presence of Keyboard in KBC port.
0E	Testing and initialization of different Input Devices. Also, update the
	Kernel Variables.
	Traps the INT09h vector, so that the POST INT09h handler gets
	control for IRQ1. Uncompress all available language, BIOS logo, and
	Silent logo modules.
13	Early POST initialization of chipset registers.
24	Uncompress and initialize any platform specific BIOS modules.
30	Initialize System Management Interrupt.
2A	Initializes different devices through DIM.
	See DIM Code Checkpoints section of document for more information.
2C	Initializes different devices. Detects and initializes the video adapter
	installed in the system that have optional ROMs.
2E	Initializes all the output devices.
31	Allocate memory for ADM module and uncompress it. Give control to
	ADM module for initialization. Initialize language and font modules for
	ADM. Activate ADM module.
33	Initializes the silent boot module. Set the window for displaying text
	information.
37	Displaying sign-on message, CPU information, setup key message,
	and any OEM specific information.
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