85
7521
7521
N/B MAINTENANCE
N/B MAINTENANCE
6. Maintenance Diagnostics
6.2 Error Codes : Following is a list of error codes in sequent display on the PIO debug board.
SYSTEM SOFT BIOS:
CODE
DESCRIPTION
01h
Start of boot loader sequence.
02h
Initialize chipset.
03h
Memory Sizing.
Perform conventional RAM(1st 640K) test with crossed-
04h
pattern R/W
05h
Move boot loader to the RAM.
06h
Start point of execution of boot loader in RAM.
07h
Shadow system BIOS.
08h
Initialize clock synthesizer
09h
Initialize audio controller.
0Ah
Detect internal ISA MODEM
0Bh
Proceed with normal boot
0Ch
Proceed with crisis boot
0Fh
DRAM sizing
10h
Initial L1,L2 cache, make stack and diagnose CMOS.
11h
Turn off fast A20 for post. Reset GDT's, 8259s quickly.
12h
Signal power on reset at COMS.
13h
Initialize the chipset, (SDRAM).
14h
Search for ISA bus VGA adapter
15h
Reset counter/timer 1, exite the RAM.
16h
User register config through CMOS
18h
Dispatch to 1st 64K RAM test
19h
Checksum the ROM
1Ah
Reset PIC's(8259s)
1Bh
Initialize video adapter(s)
1Ch
Initialize video (6845 regs)
CODE
DESCRIPTION
1Dh
Initialize color adapter
1Eh
Initialize monochrome adapter
1Fh
Test 8237A page registers
20h
Perform keyboard self test
21h
Test & initialize keyboard controller
22h
Check if CMOS RAM valid
23h
Test battery fail & CMOS X-SUM
24h
Test the DMA controllers
25h
Initialize 8237A controller
26h
Initialize interrupt vectors table.
27h
RAM quick sizing
28h
Protected mode entered safely
29h
RAM test completed
2Ah
Protected mode exit successful
2Bh
Setup shadow
2Ch
Prepare to initialize video
2Dh
Search for monochrome adapter
2Eh
Search for color adapter, VGA initialize.
2Fh
Signon messages displayed
30h
Special init of keyboard ctlr
31h
Test if keyboard present
32h
Test keyboard interrupt
33h
Test keyboard command Byte
34h
Test, blank and count all RAM
35h
Protected mode entered safely (2).
36h
RAM test complete