Compaq XL118-XL127 Laptop User Manual


 
P
RESARIO
N
OTEBOOK
M
AINTENANCE
AND
S
ERVICE
G
UIDE
1200XL S
ERIES
T
ROUBLESHOOTING
35
Presario 1200 Series
Models: XL101-XL113, XL115, XL118-XL127
12h Restore CPU control word during warm boost
13h Initialize PCI Bus Mastering devices
14h Initialize keyboard controller
16h 1-2-2-3 BIOS ROM Checksum
17h Initialize cache before memory autosize
18h 8254 timer initialization
1Ah 8237 DMA controller initialization
1Ch Reset Programmable Interrupt Controller
20h Test DRAM refresh
22h Test 8742 Keyboard Controller
24h Set ES segment register to 4 GB
26h Enable A20 line
28h Autosize DRAM
29h Initialize POST Memory Manager
2Ah Clear 512 KB base RAM
2Ch RAM failure on address line xxxx*RAM failure on data
bits xxxx* of low byte of memory bus
2Eh Enable cache before system BIOS shadow
2Fh RAM failure on data bits xxxx*of high byte memory bus
30th Test CPU bus-clock frequency
32h Initialize Phoenix Dispatch Manager
33h Warm start shut down
36h Shadow system BIOS ROM
38h Autosize cache
3Ah Advanced configuration of chipset registers
3Ch Load alternate registers with CMOS values
3Dh Initialize interrupt vectors
42h POST device initialization
45h Check ROM copyright notice
46h Check Video configuration against CMOS
48h Initialize PCI bus and devices
Code Beeps POST Routine Description