Toshiba Satellite M35 Series, Maintenance Manual

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2 Troubleshooting Procedures 2.4 System Board Troubleshooting
Table 2-4 Debugging port boot mode status (2/7)
Debug Port Description
0098h Initialize USB Controller
0101h
0102h Verify Real Mode. If the CPU is in protected mode, turn on A20 and pulse the
reset line, forcing a shutdown 0.
0103h Disable Non-Maskable Interrupts.
0104h Get CPU type from CPU registers and save it.
0106h Initialize system hardware. Reset the DMA controllers, disable the videos, clear
any pending interrupts from the real-time clock and set up port B register.
0107h Disable system ROM shadow and start to execute ROM code from the flash part.
0108h Initialize chip set registers to the initial values.
0109h Set in-POST flag in CMOS that indicates we are in POST.
010Ah Initialize CPU registers.
010Bh
010Ch Initialize cache.
010Eh
010Fh
0110h
0111h Load alternate registers with initial table values
0112h Restore the contents of the CPU control word whenever the CPU is reset.
0113h Reset PCI devices in early post
0114h
0116h Verify that the ROM BIOS checksums to zero
0117h Initialize external cache before autosizing memory.
0118h Initialize PIT(Programmable Interval Timer).
011Ah Initialize DMA.
011Ch Initialize interrupt controllers for some shutdowns.
011Fh
0120h Verify that DRAM refresh is operating by polling the refresh bit in PORTB.
0122h
0124h Set segment-register addressibility to 4 GB
0128h Determine DRAM size and configure the chipset accordingly. Before autosizing,
all caches and all shadow RAM are disabled.
2-22 Satellite M30-35 Maintenance Manual (960-455)