Toshiba Satellite U300 Series Maintenance Manual page 68

2 Troubleshooting Procedures
13h Initialize PCI Bus Mastering devices
Code Beeps POST Routine Description
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 1-3-1-1 Test DRAM refresh
22h 1-3-1-3 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 1-3-4-1 RAM failure on address line xxxx*
2Eh 1-3-4-3 RAM failure on data bits xxxx* of low byte of memory bus
2Fh Enable cache before system BIOS shadow
30h 1-4-1-1 RAM failure on data bits xxxx* of high byte of memory bus
32h Test CPU bus-clock frequency
33h Initialize Phoenix Dispatch Manager
36h Warm start shut down
38h Shadow system BIOS ROM
3Ah Autosize cache
3Ch Advanced configuration of chipset registers
3Dh Load alternate registers with CMOS values
42h Initialize interrupt vectors
45h POST device initialization
46h 2-1-2-3 Check ROM copyright notice
48h Check video configuration against CMOS
49h Initialize PCI bus and devices
4Ah Initialize all video adapters in system
4Bh QuietBoot start (optional)
4Ch Shadow video BIOS ROM
4Eh Display BIOS copyright notice
50h Display CPU type and speed
51h Initialize EISA board
52h Test keyboard
54h Set key click if enabled
58h 2-2-3-1 Test for unexpected interrupts
59h Initialize POST display service
5Ah Display prompt "Press F2 to enter SETUP"
5Bh Disable CPU cache
5Ch Test RAM between 512 and 640 KB
60h Test extended memory
62h Test extended memory address lines
Satellite U300 and Satellite Pro U300 Maintenance Manual (960-Q08) 17