Appendix
Appendix B
B-1 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 | |
| - | |
| - | |
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 | 1. | Blank out screen |
| 2. | Clear CMOS error flag |
06h | Reserved | |
07h | 1. | Clear 8042 interface |
| 2. | Initialize 8042 |
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. |
Reserved | ||
0Eh | Test F000h segment shadow to see whether it is | |
| 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 | |
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 |