Toshiba S4 manual PIT#0

2.4 System Board Troubleshooting 2 Troubleshooting Procedures

Table 2-4 Printer port LED boot mode status (4/9)

LED Status	Test item	Contents
(03h)		Expansion memory checksum check
		resume error (Resume error LED=76H)
		PnP RAM checksum check (Resume
		error LED=77H)
		Transition to RESUME-MAIN
	Resume error process	Reset of CPU clock to low
		Prohibition of all SMI
		Clearance of resume status
		Return to ROM
		Turning area of C0000h to EFFFFh to PCI
		(Prohibition of DRAM)
		Setting of resume error request
	Copying ROM/RAM of system BIOS	(HLT, when error occurs)
04h	Security check
05h	SMRAM initialization
	APIC initialization
	WakeUp factor check
	SMRAM base rewriting and CPU state
	map saving for BIOS
	Permission of SMI based on ASMI
06h	Initialization of devices which need	PIT test (Cold boot only) and initialization
	initialization before PCI bus initialization.
		Setting of test pattern to channel 0 of
		PIT#0
		Check whether the set test pattern can be
		read
		Initialization of PIT channel 0, Setting of
		timer interruption interval to 55ms
		Initialization of PIT channel 2, Setting of
		the sound generator frequency to 664Hz
		Test of PIT channel 1 (Check whether the
		refresh signal works normally in 30 micro-
		s refresh interval.) HLT, when the time is
		out.
		Test of PIT channel 2 (Check whether the
		speaker gate works normally.)
		CPU clock measurement
		Check of parameter block A
		Permission of SMI except auto-off function
		Judging of destination (Japan or except
		Japan) based on DMI data

TECRA S3 Maintenance Manual (960-532) [CONFIDENTIAL] 2-23