TYAN S3970, Manual

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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.