Acer G520 series manual Appendix F Diagnostic Code Checkpoints

166			Appendix F: Diagnostic Code Checkpoints
	Diagnostic LED Decoder
Check
	G=Green, R=Red, A+Amber				Description
point
	MSB			LSB
78	G	R	R	R	Initializes IPL devices
					controlled by BIOS and
					option ROMs.
7A	G	R	A	R	Intializes remaining
					option ROMs.
7C	G	A	R	R	Generate and write
					contents of ESCD in
					NVRam.
84	R	G	OFF	OFF	Log errors encountered
					during POST.
85	R	G	OFF	G	Display errors to the user
					and get the user response
					for error.
87	R	G	G	G	Execute BIOS setup if
					needed/requested.
8C	A	G	OFF	OFF	Late POST initialization of
					chipset registers.
8D	A	G	OFF	G	Build ACPI tables (if ACPI
					supported).
8E	A	G	G	OFF	Program the peripheral
					parameters. Enable/
					Disable NMI as selected
90	R	OFF	OFF	R	Late POST initialization of
					system management
					interrupt.
A0	R	OFF	R	OFF	Check boot password if
					installed
A1	R	OFF	R	G	Clean-up work needed
					before booting to
					operating system.