2.4 System Board Troubleshooting

2 Troubleshooting Procedures

 

 

 

Table 2-3 D port status (1/9)

 

 

 

 

 

 

 

D port

 

Inspection items

Details

 

 

status

 

 

 

 

 

 

 

 

 

Enabling address line A20 and Clearing a

 

 

 

 

software reset bit

 

 

 

 

Prohibition of APIC

 

 

 

 

 

 

 

 

 

Initializing MCHM

 

 

 

 

 

 

 

 

 

Initializing ICHM

 

 

 

 

 

 

 

 

 

Initializing Super I/O

 

 

 

 

 

 

 

 

 

Initializing debug port

 

 

 

 

 

 

 

 

 

Dummy read of 3rd Bus data

 

 

 

 

Setting of printer port

(Only for the model supporting PRT)

 

 

 

 

 

 

 

F000H

BTBK_START

 

 

 

 

 

 

 

 

 

Initializing the CH0 of a PIT

(For HOLD_ON)

 

 

 

 

 

 

 

 

Initializing flags determining whether BIOS

 

 

 

 

is rewritten

 

 

 

 

 

 

 

 

 

CHECK SUM CHECK

Switching to protected mode

 

 

 

 

 

 

 

 

 

 

 

Examining the checksum of Boot Block

 

 

 

 

 

(Skip when returned to S3)

 

 

 

 

 

HLT when check sum error

 

 

 

 

 

Examining the checksum other than Boot

 

 

 

 

 

Block

 

 

 

 

 

 

 

F001H

BTBK_CALC_CHKSUM_END

 

 

 

 

 

 

 

 

 

 

EC/KBC

rewrite check

BIOS rewrite when “rewrite” is requested

 

 

 

 

 

 

 

 

 

 

 

Transition of the process to System BIOS IRT

 

 

 

 

 

when returned to S3

 

 

 

 

 

 

 

 

 

Key input

 

 

 

 

 

 

 

 

 

 

When inputting key, [ ],

 

 

 

 

[

],

 

 

 

 

[TAB] key check

 

 

 

F002H

BTBK_INI_SC_START

 

 

 

 

 

 

 

 

 

Initializing security controller

 

 

 

 

 

 

 

 

F003H

BTBK_INI_SC_ERR

 

 

 

 

 

 

 

 

F004H

BTBK_SC_HW_FAILURE

 

 

 

 

 

 

 

 

F005H

BTBK_INI_KBC_END

 

 

 

 

 

 

 

 

 

Checking whether BIOS rewrite is

CheckSum error except Boot Block

 

 

 

requested

when rewrite is requested by user

 

 

 

 

 

Transition to BIOS rewrite

 

 

 

 

 

 

 

F006H

BTBK_ENTER_CHK_BIOS_SIGN

 

 

 

 

 

 

 

 

 

BIOS signature check

 

 

 

 

 

 

 

 

Satellite A50S/TECRA A3X Maintenance Manual (960-534)

[CONFIDENTIAL]

2-19

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Toshiba A3X manual Port Inspection items Details Status