Toshiba Tecra A8 Maintenance Manual - Page 82

2 Troubleshooting Procedures 2.4 System Board Troubleshooting [ATI chipset model] Table 2-4-2 Debug port (Boot mode) error status (1/9) D port status Inspection items Details Boot block Permission of A20 line and clear of software reset bit Prohibition of APIC Initialization of North Bridge and South Bridge Initialization of Super I/O Initialization of debug port Dummy read of EC 3rd Bus data Initialization of only PIT CH0 Setting of printer port (only for models supporting printer port) CHECK SUM CHECK Transition to Protect mode F000 F001 F002 F005 F006 F007 Boot block checksum (skip when returned to S3) (halts, when error) Checksum other than boot block (skip when returned to S3) EC/KBC rewrite check If "rewrite" is requested, go to "BIOS rewrite process" Initialization of SC When error, holts. DPORT=F003H or F004H Key input (skip when returned to S3) When a key pressed ,check the key (skip when returned to S3) Enables CPU cache Security check BIOS rewrite request check If Checksum check error occurred on except Boot Block or rewrite is required by user, go to "BIOS rewrite process". Transits to System BIOS IRT BIOS rewrite process Initialization of South Bridge Configuration of DRAM Permission of cache (L1 cache only) Memory clear Transition to real mode and copy of BIOS to RAM 2-34 [CONFIDENTIAL] TECRA A8 /Satellite Pro A120 Maintenance Manual (960-573)