| Code
|
Meaning
|
| C0
|
1.Turn
off OEM specific cache, shadow
2.Initialize
standard devices with default values:
DMA
controller (8237)
Programmable
Interrupt Controller (8259)
Programmable
Interval Timer (8254)
RTC
chip |
| C1
|
Auto
detection of onboard DRAM & Cache |
| C3
|
1.
Test the first 256K DRAM
2. Expand
the compressed codes into temporary DRAM area including
the compressed system BIOS & Option ROMs
|
| C5
|
Copy
the BIOS from ROM into E000FFFF shadow RAM so that
POST will go faster |
| 01-02
|
Reserved
|
| 03
|
Initialize
EISA registers (EISA BIOS only) |
| 04
|
Reserved
|
| 05
|
1.
Keyboard Controller Self Test
2. Enable
Keyboard Interface |
| 06
|
Reserved
|
| 07
|
Verifies
CMOS's basic R/W functionality |
| BE
|
Program
defaults values into chipset according to the MODBINable
Chipset Default Table |
| 09
|
1.Program
configuration register of Cyrix CPU according to the
MODBINable Cyrix Register Table
2.OEM
specific cache initialization |
| 0A
|
1.Initialize
the first 32 interrupt vectors with corresponding
interrupt handlers
Initialize
INT No from 33120 with Dummy (Spurious) interrupt
handler
2.Issue
CPUID instruction to identify CPU type
3.Early
Power Management initialization (OEM specific)
|
| 0B
|
1.Verify
the RTC time is valid or not
2.Detect
bad battery
3.Read
CMOS data into BIOS stack area
4.PnP
initializations including (PnP BIOS only)
Assign
CSN to PnP ISA card
Create
resource map from ESCD
5.Assign
IO & Memory for PCI devices (PCI BIOS only)
|
| 0C
|
Initialization
of the BIOS data area (40:040:FF) |
| 0D
|
1.Program
some of the chipset's value according to setup.(Early
setup value program)
2.Measure
CPU speed for display & decide the system clock
speed
3.Video
initialization including Monochrome, CGA, EGA/VGA
If no
display device found, the speaker will beep.
|
| 0E
|
1.Initialize
the APIC (MultiProcessor BIOS only)
2.Test
video RAM (If Monochrome display device found)
3.Show
message including:
Award
logo
Copyright
string
BIOS
date code & Part No
OEM
specific sign on messages
Energy
Star logo (Green BIOS only)
CPU
brand, type & speed |
| 0F
|
DMA
channel 0 test |
| 10
|
DMA
channel 1 test |
| 11
|
DMA
page registers test |
| 12-13
|
Reserved
|
| 14
|
Test
8254 timer 0 counter 2 |
| 15
|
Test
8259 interrupt mask bits for channel 1 |
| 16
|
Test
8259 interrupt mask bits for channel 2 |
| 17
|
Reserved
|
| 19
|
Test
8259 functionality |
| 1A-1D
|
Reserved
|
| 1E
|
If
EISA NVM checksum is good, execute EISA initialization
(EISA BIOS only) |
| 1F-29
|
Reserved
|
| 30
|
Get
base memory & extended memory size |
| 31
|
1.Test
base memory from 256K to 640K
2.Test
extended memory from 1M to the top of memory
|
| 32
|
1.Display
the Award Plug & Play BIOS extension message(PnP
BIOS only)
2.Program
all onboard super I/O chips(if any) including COM
ports, LPT ports, FDD port according to setup value
|
| 33-3B
|
Reserved
|
| 3C
|
Set
flag to allow users to enter CMOS setup utility
|
| 3D
|
1.Initialise
keyboard
2.Install
PS2 mouse |
| 3E
|
Try
to turn on level 2 cache Note: Some chipset may need
to turn on the L2 cache in this stage. But usually,
the cache is turn on later in Post 61h |
| 3F-40
|
Reserved
|
| BF
|
1.Program
the rest of the chipset's value according to setup
(later setup value program)
2.If auto
configuration is enabled, programmed the chipset with
predefined values in the MODBINable AutoTable
|
| 41
|
Initialize
floppy disk drive controller |
| 42
|
Initialize
hard drive controller |
| 43
|
If
it is a PnP BIOS, initialize serial & parallel
ports |
| 44
|
Reserved
|
| 45
|
Initialize
math coprocessor |
| 46-4D
|
Reserved
|
| 4E
|
If
there is any error detected (such as video, KB....),
show all the error messages on the screen &
wait for user to press <F1> key |
| 4F
|
1.If
password is needed, ask for password
2.Clear
the Energy Star logo (Green BIOS only) |
| 50
|
Write
all the CMOS values currently in the BIOS stack are
back into the CMOS |
| 51
|
Reserved
|
| 52
|
1.Initialize
all ISA ROMs
2.Later
PCI initializations(PCI BIOS only)
assign
IRQ to PCI devices
initialize
all PCI ROMs
3.PnP
initializations (PnP BIOS only)
assign
IO, Memory, IRQ & DMA to PnP ISA devices
initialize
all PnP ISA ROMs
4.Program
shadow RAM according to setup settings
5.Program
parity according to setup setting
6.Power
Management initialization
Enable/Disable
global PM
APM
interface initialization |
| 53
|
1.If
it is not a PnP BIOS, initialize serial & parallel
ports
2.Initialize
time value in BIOS data area by translate the RTC
time value into a timer tick value |
| 54-5F
|
Reserved
|
| 60
|
Setup
virus protection (boot sector protection) functionality
according to setup setting |
| 61
|
1.Try
to turn on level 2 cache (if L2 cache already turned
on in post 3D, this part will be skipped)
2.Set
the boot up speed according to setup setting
3.Last
chance for chipset initialization
4.Last
chance for Power Management initialization (Green
BIOS only)
5.Show
the system configuration table |
| 62
|
1.Setup
daylight saving according to setup values
2.Program
the NUM lock, typematic rate & typematic speed
according to setup setting |
| 63
|
1.If
there is any changes in the hardware configuration,
update the ESCD information (PnP BIOS only)
2.Clear
memory that have been used
3.Boot
system via INT 19h |
| FF
|
Boot
|
