Code |
Meaning |
02 |
Verify Real Mode |
04 |
Get CPU type |
06 |
Initialise system hardware |
08 |
Initialise chipset registers with initial POST values |
09 |
Set in POST flag |
0A |
Initialise CPU registers |
0C |
Initialise cache to initial POST values |
0E |
Initialise I/O |
10 |
Initialise power management |
11 |
load alternate registers with initial POST values |
12 |
Jump to User Patch 0 |
14 |
Initialise keyboard controller |
16 |
BIOS ROM checksum |
18 |
8254 timer initialisation |
1A |
8237 DMA controller initialisation |
1C |
Reset PIC |
20 |
Test DRAM refresh |
22 |
Test 8742 keyboard controller |
24 |
Set ES segment register to 4 Gb |
26 |
Enable Address Line A20 |
28 |
Autosize DRAM |
2A |
Clear 512K base RAM |
2C |
Test 512K base address lines |
2E |
Test 512K base memory |
30 |
Test base address memory |
32 |
Test CPU bus clock frequency |
34 |
Test CMOS RAM |
35 |
Test chipset register initialise |
36 |
Test check resume |
37 |
Reinitialise the chipset |
38 |
Shadow System BIOS ROM |
39 |
Reinitialise the cache |
3A |
Autosize the cache |
3C |
Configure advanced chipset registers |
3D |
Load alternate registers with CMOS values |
3E |
Read hardware configuration from keyboard controller |
40 |
Set initial CPU speed |
42 |
Initialise interrupt vectors |
44 |
Initialise BIOS interrupts |
46 |
Check ROM copyright notice |
47 |
Initialise manager for PCI option ROMs |
48 |
Check video configuration against CMOS |
49 |
Initialise PCI bus and devices |
4A |
Initialise all video adapters |
4C |
Shadow video BIOS ROM |
4E |
Display copyright notice |
50 |
Display CPU type and speed |
52 |
Test keyboard |
54 |
Set key click if enabled |
56 |
Enable keyboard |
58 |
Test for unexpected interrupts |
5A |
Display prompt "Press F2 to Enter Setup" |
5C |
Test RAM between 512 and 640K |
5E |
Test base memory |
60 |
Test expanded memory |
62 |
Test extended memory address lines |
64 |
Jump to User Patch 1 |
66 |
Configure advanced cache registers |
68 |
Enable external and CPU caches |
69 |
Set up power management |
6A |
Display external cache size |
6C |
Display shadow message |
6E |
Display non-disposable segments |
70 |
Display error messages |
72 |
Check for configuration errors |
74 |
Test RTC |
76 |
Check for keyboard errors |
7A |
Enable keylock |
7C |
Set up hardware interrupt vectors |
7E |
Test coprocessor if present |
80 |
Disable onboard I/O ports |
82 |
Detect and install external RS232 ports |
84 |
Detect and install external parallel ports |
86 |
Reinitialise onboard I/O ports |
88 |
Initialise BIOS data area |
8A |
Initialise extended BIOS data area |
8C |
Initialise floppy controller |
8E |
Hard disk autotype configuration |
90 |
Initialise hard disk controller |
91 |
Initialise local bus hard disk controller |
92 |
Jump to User Patch 2 |
94 |
Disable A20 address line |
96 |
Clear huge ES segment register |
98 |
Search for option ROMs |
9A |
Shadow option ROMs |
9C |
Set up Power Management |
9E |
Enable hardware interrupts |
A0 |
Set time of day |
A2 |
Check key lock |
A4 |
Initialise typematic rate |
A8 |
Erase F2 prompt |
AA |
Scan for F2 key stroke |
AC |
Enter Setup |
AE |
Clear in-POST flag |
B0 |
Check for errors |
B2 |
POST done |
B4 |
One beep |
B6 |
Check password (optional) |
B8 |
Clear global descriptor table |
BC |
Clear parity checkers |
BE |
Clear screen (optional) |
BF |
Check virus and backup reminders |
C0 |
Try to boot with INT 19 |
D0 |
Interrupt handler error |
D2 |
Unknown interrupt error |
D4 |
Pending interrupt error |
D6 |
Initialise option ROM error |
D8 |
Shutdown error |
DA |
Extended Block Move |
DC |
Shutdown 10 error |
