Toshiba Tecra A8 Maintenance Manual page 73

2.4 System Board Troubleshooting
[Intel chipset model]
Table 2-4-1 Debug port (Boot mode) error status (1/9)
D port status
Boot block Permission of A20 line and clear of
software reset bit
Prohibition of APIC
Initialization of MCH and ICH
Initialization of Super I/O
Initialization of debug port
Dummy read of 3rd Bus data
Initialization of only PIT CH0
Setting of printer port (only for models
supporting printer port)
F000
(only for models supporting Super IO)
(only for models supporting Super IO
or not)
F001 EC/KBC rewrite check
F002 Initialization of SC
Key input (skip when returned to S3)
F005
Enables CPU cache
F006 Security check
BIOS rewrite request check
F007 Transits to System BIOS IRT
BIOS rewrite process
F008 Transition to real mode and copy of
BIOS to RAM
TECRA A8 /Satellite Pro A120 Maintenance Manual (960-573)
Inspection items
2 Troubleshooting Procedures
Details
Only PIT CH0 initialization (for HOLD_ON)
CHECK SUM CHECK
Transition to protect mode
Boot block checksum (skip when returned to S3)
(halts when error)
Checksum other than boot block (skip when
returned to S3)
If "rewrite" is requested, go to "BIOS rewrite
process"
When a key pressed ,check the key (skip when
returned to S3)
If Checksum check error occurred on except
Boot Block or rewrite is required by user, go to
"BIOS rewrite process".
Initialization of ICHM. D31
Configuration of DRAM
Permission of cache (L1 cache only)
Memory clear
[CONFIDENTIAL] 2-25