POST Code
Code | Beeps | POST Routine Description |
|
|
|
02h |
| Verify Real Mode |
|
|
|
03h |
| Disable |
|
|
|
04h |
| Get CPU type |
|
|
|
06h |
| Initialize system hardware |
|
|
|
08h |
| Initialize chipset with initial POST values |
|
|
|
09h |
| Set IN POST flag |
|
|
|
0Ah |
| Initialize CPU registers |
|
|
|
0Bh |
| Enable CPU cache |
|
|
|
0Ch |
| Initialize caches to initial POST values |
|
|
|
0Eh |
| Initialize I/O component |
|
|
|
0Fh |
| Initialize the local bus IDE |
|
|
|
10h |
| Initialize Power Management |
|
|
|
11h |
| Load alternate registers with initial POST |
|
| values |
|
|
|
12h |
| Restore CPU control word during warm boot |
|
|
|
13h |
| Initialize PCI Bus Mastering devices |
|
|
|
14h |
| Initialize keyboard controller |
|
|
|
16h | BIOS ROM checksum | |
|
|
|
17h |
| Initialize cache before memory autosize |
|
|
|
18h |
| 8254 timer initialization |
|
|
|
1Ah |
| 8237 DMA controller initialization |
|
|
|
1Ch |
| Reset Programmable Interrupt Controller |
|
|
|
20h | Test DRAM refresh | |
|
|
|
22h | Test 8742 Keyboard Controller | |
|
|
|
24h |
| Set ES segment register to 4 GB |
|
|
|
26h |
| Enable A20 line |
|
|
|
28h |
| Autosize DRAM |
|
|
|
29h |
| Initialize POST Memory Manager |
|
|
|
2Ah |
| Clear 215 KB base RAM |
|
|
|
2Ch | RAM failure on address line xxxx | |
|
|
|
2Eh | RAM failure on data bits xxxx of low byte of | |
|
| memory bus |
|
|
|
2Fh |
| Enable cache before system BIOS shadow |
|
|
|
30h | RAM failure on data bits xxxx of high byte of | |
|
| memory bus |
|
|
|
32h |
| Test CPU |
|
|
|
33h |
| Initialize Phoenix Dispatch Manager |
|
|
|
36h |
| Warm start shut down |
|
|
|
38h |
| Shadow system BIOS ROM |
|
|
|
3Ah |
| Autosize cache |
|
|
|
3Ch |
| Advanced configuration of chipset registers |
|
|
|
3Dh |
| Load alternate registers with CMOS values |
|
|
|
42h |
| Initialize interrupt vectors |
|
|
|
45h |
| POST device initialization |
|
|
|
81 | Chapter 4 |