Appendix B: Award BIOS POST Codes
POST (hex) | Description |
|
|
2Dh | 1. Initialize |
| 2. Put information on screen display, including Award title, CPU type, CPU |
| speed …. |
2Eh | Reserved |
2Fh | Reserved |
30h | Reserved |
31h | Reserved |
32h | Reserved |
33h | Reset keyboard except Winbond 977 series Super I/O chips. |
34h | Reserved |
35h | Reserved |
36h | Reserved |
37h | Reserved |
38h | Reserved |
39h | Reserved |
3Ah | Reserved |
3Bh | Reserved |
3Ch | Test 8254 |
3Dh | Reserved |
3Eh | Test 8259 interrupt mask bits for channel 1. |
3Fh | Reserved |
40h | Test 8259 interrupt mask bits for channel 2. |
41h | Reserved |
42h | Reserved |
43h | Test 8259 functionality. |
44h | Reserved |
45h | Reserved |
46h | Reserved |
47h | Initialize EISA slot |
48h | Reserved |
49h | 1. Calculate total memory by testing the last double word of each 64K page. |
| 2. Program writes allocation for AMD K5 CPU. |
4Ah | Reserved |
4Bh | Reserved |
4Ch | Reserved |
4Dh | Reserved |
4Eh | 1. Program MTRR of M1 CPU |
| 2. Initialize L2 cache for P6 class CPU & program CPU with proper cacheable |
| range. |
| 3. Initialize the APIC for P6 class CPU. |
| 4. On MP platform, adjust the cacheable range to smaller one in case the |
| cacheable ranges between each CPU are not identical. |
4Fh | Reserved |
50h | Initialize USB |
51h | Reserved |
52h | Test all memory (clear all extended memory to 0) |
53h | Reserved |
54h | Reserved |
55h | Display number of processors |
56h | Reserved |
57h | 1. Display PnP logo |
| 2. Early ISA PnP initialization |
| |
|
|
