POST - CODE
96M2831o-2 ©2003 DSM Computer AG, München
Seite: 34 Stand: November 2003
7. BIOS Reference - POST Codes
POST Code Description
01 - 02 Reserved
C0 Turn off OEM specific cache, shadow...
03 1. Initialize EISA registers (EISA BIOS only)
2. Initialize all standard devices with default values, Standard devices includes:
-DMA controller (8237)
-Programmable Interrupt Controller (8259)
-Programmable lnterval Timer (8254)
-RTC chip
04 Reserved
05 1. Keyboard Controller Self-Test
2. Enable Keyboard Interface
06 Reserved
07 Verifies CMOS basic R/W functionality
BE Program defaults values into chipset according to the MODBINable Chipset
Default table
C1 Auto-detection of onboard DRAM & Cache
C5 Copy the BIOS from ROM into E0000-FFFFF shadow RAM so that POST will
go faster
08 Test the first 256K DRAM
09 1. Program the configuration register of Cyrix CPU according to the
MODBINable Cyrix Register Table
2. OEM specific cache initialization (if needed)
0A 1. Initialize the first 32 interrupt vectors with corresponding Interrupt handlers
Initialize INT no from 33-120 with Dummy (Suprious) Interrupt Handler
2. Issue CPU ID 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 (PnP BIOS only)
0C Initialization of the BIOS Data Area
0D 1. Program some of the Chipset value according to Setup. (Early Setup Value
Program)
2. Measure CPU speed for display & decide the system clock speed
3. Video initialization including Mono, CGA, EGA/VGA. If no display device
found the speaker will beep
0E 1. Initialize the APIC (Multi-Processor BIOS only)
2. Test video RAM (lf Monochrome display device found)
3. Show messages 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
-Test system BIOS checksum (Non-Compress Version only)
0F DMA channel 0 test