Keyboard is locked out - Unlock the key.
BIOS detect the keyboard is locked. P17 of keyboard controller is pulled low.
Keyboard error or no keyboard present.
Cannot initialize the keyboard. Make sure the keyboard is attached correctly and no keys are
being pressed during the boot.
Manufacturing POST loop.
System will repeat POST procedure infinitely while the P15 of keyboard controller is pull low.
This is also used for M/B burn in test.
BIOS ROM checksum error - System halted.
The checksum of ROM address F0000H-FFFFFH is bad.
Memory test fail.
BIOS reports the memory test fail if the onboard memory is tested error.
3-13 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.
0h1
Expand the Xgroup 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
1. Clear 8042 interface
2. Initialize 8042 self-test
08h
1. Test special keyboard controller for Winbond 977 series Super I/O chips.
2. Enable keyboard interface.
09h
Reserved
0Ah
1. Disable PS/2 mouse interface (optional).
2. Auto detect ports for keyboard & mouse followed by a port & interface
swap (optional).
3. 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.
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