| Code |
Meaning |
| 02 |
Verify
real mode |
| 04 |
Get
CPU type |
| 06 |
Initialize
system hardware |
| 08 |
Initialize
chipset registers with initial POST values |
| 09 |
Set
in POST flag |
| 0A |
Initialize
CPU registers |
| 0C |
Initialize
cache to initial POST values |
| 0E |
Initialize
I/O |
| 10 |
Initialize
power management |
| 11 |
Load
alternate registers with initial POST values |
| 12 |
Jump
to UserPatch0 |
| 14 |
Initialize
keyboard controller |
| 16 |
BIOS
ROM checksum |
| 18 |
8254
programmable interrupt timer initialization |
| 1A |
8237
DMA controller initialization |
| 1C |
Reset
8254 programmable interrupt timer |
| 20 |
Test
DRAM refresh |
| 22 |
Test
8742 keyboard controller |
| 24 |
Set
ES segment register to 4GB |
| 28 |
Autosize
DRAM |
| 2A |
Clear
512K base RAM |
| 2C |
Test
512K base address lines |
| 2E |
Test
512K base memory |
| 32 |
Test
CPU bus-clock frequency |
| 37 |
Reinitialize
the chipset |
| 38 |
Shadow
system BIOS ROM |
| 39 |
Reinitialize
the cache |
| 3A |
Autosize
cache |
| 3C |
Configure
advanced chipset registers |
| 3D |
Load
alternate registers with CMOS values |
| 40 |
Set
initial CPU speed |
| 42 |
Initialize
interrupt vectors |
| 44 |
Initialize
BIOS interrupts |
| 46 |
Check
ROM copyright notice |
| 48 |
Check
video configuration against CMOS |
| 49 |
Initialize
PCI bus and devices |
| 4A |
Initialize
all video adapters in system |
| 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 512K and 640K |
| 60 |
Test
expanded memory |
| 62 |
Test
extended memory address lines |
| 64 |
Jump
to UserPatch1 |
| 66 |
Configure
advanced cache registers |
| 68 |
Enable
external and CPU caches |
| 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
real time clock |
| 76 |
Check
for keyboard errors |
| 7C |
Setup
hardware interrupts 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 |
Re-initialize
on-board I/O ports |
| 88 |
Initialize
BIOS data area |
| 8A |
Initialize
extended BIOS data area |
| 8C |
Initialize
floppy controller |
| 90 |
Initialize
hard disk controller |
| 91 |
Initialize
local bus hard disk controller |
| 92 |
Jump
to UserPatch2 |
| 94 |
Disable
A20 address line |
| 96 |
Clear
huge ES segment register |
| 98 |
Search
for option ROM's |
| 9A |
Shadow
option ROM's |
| 9C |
Setup
power management |
| 9E |
Enable
hardware interrupts |
| A0 |
Set
time of day |
| A2 |
Check
key lock |
| A8 |
Erase
F2 prompt |
| AA |
Scan
for F2 keystroke |
| AC |
Enter
setup |
| AE |
Clear
in-POST flag |
| B0 |
Check
for errors |
| B2 |
POST
done; prepare to boot operating system |
| 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 interrupt 19 |
| D0 |
Interrupt
handler error |
| D2 |
Unknown
interrupt error |
| D4 |
Pending
interrupt error |
| D6 |
Initialize
option ROM error |
| D8 |
Shutdown
error |
| DA |
Extended
block move |
| DC |
Shutdown
10 error |
| E2 |
Initialize
the chipset |
| E3 |
Initialize
refresh counter |
| E4 |
Check
for forced flash |
| E5 |
Check
HW status of ROM |
| E6 |
BIOS
ROM is ok |
| E7 |
Do
a complete RAM test |
| E8 |
Do
OEM initialization |
| E9 |
Initialize
interrupt controller |
| EA |
Read
in bootstrap code |
| EB |
Initialize
all vectors |
| EC |
Boot
the flash program |
| ED |
Initialize
the boot device |
| EE |
Boot
code was read ok |
