E-2Service GuideTable E-1 POST Checkpoint List (Continued)
Checkpoint Description
2Ch 128K base memory testing
Set default SS:SP= 0:400
Note: The 128K base memory area is tested for POST execution. The remaining
memory area is tested later.
20h KB controller(8041/8042) testing
KB type determination
Write default command byte upon KB type
24h PIC(8259) testing & initialization
30h System Shadow RAM
34h DRAM sizing
3Ch Initialize interrupt vectors
4Bh Identify CPU brand and type
35h PCI pass 0
40h Assign I/O if device request
41h Assign Memory if device requested
44h Assign IRQ if device request
45h Enable command byte if device is OK
51h DownLoad keyboard matrix
50h Initialize Video display
4Ch ChipUp initialization for CPU clock checking
54h Process VGA shadow region
58h Set POST screen mode(Graphic or Text)
Display Acer(or OEM) logo if necessary
Display Acer copyright message if necessary
Display BIOS serial number
5Ch Memory testing
5Ah SMRAM test and SMI handler initialization
4Eh Audio initialization
60h External Cache sizing
External Cache testing(SRAM & Controller)
Enable internal cache if necessary
Enable external cache if necessary
64h Reset KB device
Check KB status
Note: The keyboard LEDs should flash once.