Toshiba qosmio f10 manual Debug port Boot mode error status 1/9, Check SUM Check

2.4 System Board Troubleshooting 2 Troubleshooting Procedures

Table 2-4 Debug port (Boot mode) error status (1/9)

D port status	Inspection items	Details
	Permission of A20 and Clear of
	software reset bit
	Prohibition of APIC
	Initialization of MCHM, ICHM
	Initialization of Super I/O
	Initialization of debug port
	Dummy read of 3rd Bus data
	Setting of printer port (for models
	supporting printer)
F000h	PIT CH0 initialization (for
	HOLD_ON)
	BIOS rewrite factor flag
	initialization
	CHECK SUM CHECK	Transition to protected mode
		Boot block checksum (skipped when
		returned to S3)
		Halts when error occurs
		Checksum other than boot block (skip
		when returned to S3)
F001h	EC/KBC rewrite check	If “rewrite” is requested, go to “BIOS rewrite
		process”.
	Transition of process to System
	BIOS IRT when returned to S3
	Key input	When a key is pressed, check if it is Tilde
		key or Tab key.
F002h	BIOS rewrite request check	If Checksum check error occurred on
		except Boot Block or rewrite is required by
		user, go to “BIOS rewrite process”.
F003h	Transits to System BIOS IRT.
	BIOS rewrite process	Initialization of ICHM. D31
		DRAM configuration
		Permission of cache (L1 cache only)
		Memory clear
		Transition to real mode and copy of BIOS
		to RAM

2-20 QOSMIO F10 Maintenance Manual (960-498)