6. Appendix
88
IPC-BX955 User’s manual
POST Codes
Table 6.3. POST Codes
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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.
0h1
Expand the X group codes locating in physical address 1000:0
02h
Reserved
03h
Initial Superio_Early_Init switch.
04h
Reserved
05h
1. Blank out screen
2. Clear CMOS error flag
06h
Reserved
07h
Clear 8042 interface
Initialize 8042 self-test
08h
Test special keyboard controller for Winbond 977 series Super I/O chips.
Enable keyboard interface.
09h
Reserved
0Ah
Disable PS/2 mouse interface (optional).
Auto detect ports for keyboard & mouse followed by a port & interface swap (optional).
Reset keyboard for Winbond 977 series Super I/O chips.
0Bh
Reserved
0Ch
Reserved
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 detects 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