8. BIOS Setup

SPI-8451-LLVA, SPI-8452-LLVA, SPI-8451-LVA 111

POST Codes
POST
(hex)
Description
CFh Test CMOS R/W functionality.
C0h Early chipset initialization:
-Disable shadow RAM
-Disable L2 cache (socket 7 or below)
-Program basic chipset registers
C1h Detect memory
-Auto-detection of DRAM size, type and ECC.
-Auto-detection of L2 cache (socket 7 or below)
C3h Expand compressed BIOS code to DRAM
C5h Call chipset hook to copy BIOS back to E000 & F000 shadow RAM.
01h Expand the Xgroup codes locating in physical address 1000:0
02h Reserved
03h Initial Superio_Early_Init switch.
04h Reserved
05h Call chipset hook to copy BIOS back to E000 & F000 shadow RAM.
06h Expand the Xgroup codes locating in physical address 1000:0
07h Reserved
08h Initial Superio_Early_Init switch.
09h Reserved
0Ah 1. Blank out screen
2. Clear CMOS error flag
0Bh Reserved
0Ch 1. Clear 8042 interface
2. Initialize 8042 self-test
0Dh Reserved
0Eh Test F000h segment shadow to see whether it is R/W-able or not. If test fails, keep beeping the
speaker.
0Fh Reserved
10h Auto detect flash type to load appropriate flash R/W codes into the run time area in F000 for
ESCD & DMI support.
11h Reserved
12h Use walking 1’s algorithm to check out interface in CMOS circuitry. Also set real-time clock
power status, and then check for override.
13h Reserved
14h Program chipset default values into chipset. Chipset default values are MODBINable by OEM
customers.
15h Reserved
16h Initial Early_Init_Onboard_Generator switch.
17h Reserved
18h Detect CPU information including brand, SMI type (Cyrix or Intel®) and CPU level (586 or
686).
19h Reserved
1Ah Reserved
1Bh Initial interrupts vector table. If no special specified, all H/W interrupts are directed to
SPURIOUS_INT_HDLR & S/W interrupts to SPURIOUS_soft_HDLR.
1Ch Reserved
1Dh Initial EARLY_PM_INIT switch.
1Eh Reserved
1Fh Load keyboard matrix (notebook platform)