Chassis Plans ATXP-965Q, Техническое описание

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ATXP-965Q Technical Reference Appendix D – Flash BIOS Programming & POST Codes
Chassis Plans 65
Appe n dix D Fla sh BI OS Pr ogr a m m in g a n d Code s
The ATXP-965Q offers the standard FLASH BIOS. When installed, you will be able to update your
BIOS without having to replace the EEPROM. The AMIBIOS8 will read the new BIOS file from a
floppy disk during boot and replace the old BIOS. When updating your BIOS, make sure you have a
disk with the correct BIOS file (its size should be 8Mb (512kB)) named AMIBOOT.ROM.
How to Reflash the BIOS
Insert a floppy containing AMIBOOT.ROM into floppy A: Please never turn the power off while
reprogramming a FLASH BIOS. While powering on, press CTRL-Home simultaneously. The board
will reboot after completion. You can also follow the process through the POST codes on Table B-2.
Alternatively the software AFUDOS can be used to reflash the BIOS.
Troubleshooting POST
AMIBIOS8 writes progress codes, also known as POST codes, to I/O port 80h during POST, in order
to provide information to OEM developers about system faults. These POST codes may be
monitored by the On-board POST Display.
Table B-1 Boot block Initialization Code Checkpoints
The Boot block initialization code sets up the chipset, memory and other components before system
memory is available. The following table describes the type of checkpoints that may occur during the
boot block initialization portion of the BIOS:
Checkpoint Description
Before D0 If boot block debugger is enabled, CPU cache-as-RAM functionality is enabled at this
point. Stack will be enabled from this point.
D0 Early Boot Strap Processor (BSP) initialization like microcode update, frequency and
other CPU critical initialization. Early chipset initialization is done.
D1 Early super I/O initialization is done including RTC and keyboard controller. Serial port is
enabled at this point if needed for debugging. NMI is disabled. Perform keyboard
controller BAT test. Save power-on CPUID value in scratch CMOS. Go to flat mode with
4GB limit and GA20 enabled.
D2 Verify the boot block checksum. System will hang here if checksum is bad.
D3 Disable CACHE before memory detection. Execute full memory sizing module. If
memory sizing module not executed, start memory refresh and do memory sizing in Boot
block code. Do additional chipset initialization. Re-enable CACHE. Verify that flat mode
is enabled.
D4 Test base 512KB memory. Adjust policies and cache first 8MB. Set stack.
D5 Boot block code is copied from ROM to lower system memory and control is given to it.
BIOS now executes out of RAM. Copies compressed boot block code to memory in right
segments. Copies BIOS from ROM to RAM for faster access. Performs main BIOS
checksum and updates recovery status accordingly.
D6 Both key sequence and OEM specific method is checked to determine if BIOS recovery is
forced. If BIOS recovery is necessary, control flows to checkpoint E0. See Boot block
Recovery Code Checkpoints section of document for more information.