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POST Code | Description |
18h | 8254 timer initialization |
1Ah | 8237 DMA controller initialization |
1Ch | Reset Programmable Interrupt Controller |
20h | |
22h | |
24h | Set ES segment register to 4 GB |
28h | Auto size DRAM |
29h | Initialize POST Memory Manager |
2Ah | Clear 512 kB base RAM |
2Ch | |
2Eh | |
| memory bus |
2Fh | Enable cache before system BIOS shadow |
32h | Test CPU |
33h | Initialize Phoenix Dispatch Manager |
36h | Warm start shut down |
38h | Shadow system BIOS ROM |
3Ah | Auto size cache |
3Ch | Advanced configuration of chipset registers |
3Dh | Load alternate registers with CMOS values |
41h | Initialize extended memory for RomPilot |
42h | Initialize interrupt vectors |
45h | POST device initialization |
46h | |
47h | Initialize I20 support |
48h | Check video configuration against CMOS |
49h | Initialize PCI bus and devices |
4Ah | Initialize all video adapters in system |
4Bh | QuietBoot start (optional) |
4Ch | Shadow video BIOS ROM |
4Eh | Display BIOS copyright notice |
4Fh | Initialize MultiBoot |
50h | Display CPU type and speed |
51h | Initialize EISA board |
52h | Test keyboard |
54h | Set key click if enabled |
55h | Enable USB devices |
58h | |
59h | Initialize POST display service |
5Ah | Display prompt “Press F2 to enter SETUP” |
5Bh | Disable CPU cache |