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35 Service Guide
Table 12.2
POST Progress Code Table
Diagnostic LED
Decoder
G=Green, R=Red,
A=Amber
Hi Low
Description
20h
Off
Off
R
Off
Uncompress various BIOS Modules.
22h
Off
Off
A
Off
Verify password Checksum.
24h
Off
G
R
Off
Verify CMOS Checksum.
26h
Off
G
A
Off
Read Microcode updates from BIOS ROM.
28h G
Off
R
Off
Initializing the processors. Set up processor registers. Select least featured
processor as the BSP.
2Ah
G
Off
A
Off
Go to Big Real Mode.
2Ch
G
G
R
Off
Decompress INT13 module.
2Eh G G A Off
Keyboard Controller Test: The keyboard controller input buffer is free. Next,
issuing the BAT command to the keyboard controller.
30h
Off
Off
R
R
Keyboard/Mouse port swap, if needed.
32h Off
Off A R
Write Command Byte 8042: The initialization after the keyboard controller BAT
command test is done. The keyboard command byte will be written next.
34h Off G R R
Keyboard Init: The keyboard controller command byte is written. Next, issuing
the pin 23 and 24 blocking and unblocking commands.
36h
Off
G
A
R
Disable and initialize 8259.
38h
G
Off
R
R
Detect Configuration Mode, such as CMOS clear.
3Ah G
Off A R
Chipset
Initialization before CMOS initialization.
3Ch G G R R
Init System Timer: The 8254 timer test is over. Starting the legacy memory
refresh test next.
3Eh G G A R
Check Refresh Toggle: The memory refresh line is toggling. Checking the 15
second on/off time next.
40h
Off
R
Off
Off
Calculate CPU speed.
42h
Off
R
G
Off
Init interrupt Vectors: Interrupt vector initialization is done.
44h
Off
A
Off
Off
Enable USB controller in chipset.
46h
Off
A
G
Off
Initialize SMM handler. Initialize USB emulation.
48h
G
R
Off
Off
Validate NVRAM areas. Restore from backup if corrupted.
4Ah G R G
Off
Load defaults in CMOS RAM if bad checksum or CMOS clear jumper is
detected.
4Ch
G
A
Off
Off
Validate date and time in RTC.
4Eh
G
A
G
Off
Determine number of micro code patches present.
50h
Off
R
Off
R
Load Micro Code To All CPUs.
52h
Off
R
G
R
Scan SMBIOS GPNV areas.
54h
Off
A
Off
R
Early extended memory tests.
56h Off A G R Disable
DMA.
58h
G
R
Off
R
Disable video controller.
5Ah
G
R
G
R
8254 Timer Test on Channel 2.
5Ch G A Off R
Enable 8042. Enable timer and keyboard IRQs. Set Video Mode: Initialization
before setting the video mode is complete. Configuring the monochrome mode
and color mode settings next.
Summary of Contents for EXPRESS5800/120Rd-1
Page 1: ... EXPRESS5800 120Rd 1 S e r v i c e G u i d e ...
Page 3: ...Revision Record Edition COMP Date Page Description 1 0 2003 1 16 First Edition ...
Page 4: ...II Service Guide ...
Page 18: ...XVI Service Guide ...
Page 52: ...32 Service Guide 12 Appendix 12 1 Block Diagram System Block Diagram ...
Page 53: ...33 Service Guide Power Block Diagram ...
Page 67: ...47 Service Guide Figure 12 10 CRS Cable xx ...
Page 68: ......
Page 69: ......
Page 70: ... ...