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Bios post checkpoint codes – Acer Altos R710 User Manual

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BIOS POST Checkpoint Codes

The following table describes the checkpoints and associated
beep codes, if any, that may occur during the POST portion of
the BIOS

.

Checkpoint
Code

Beep Code

Description

01h

One short
beep before
boot

02h

Verify Real Mode. If the CPU is in protected
mode, turn on A20 and pulse the reset line,
forcing a shutdown 0.
NOTE: Hook routine should not alter DX,
which holds the powerup CPUID.

03h

Disabel Non-Maskable Interrupts (NMI).

04h

Get CPU type from CPU registers and other
methods.
Save CPU type in NVRAM.
NOTE: Hook routine should not alter DX,
which holds the powerup CPUID.

06h

Initialize system hardware. Reset the DMA
controllers, disable video, clear any pending
interrupts from the real-time clock and
setup port B register.

07h

Disable system ROM shadow and start to
execute ROMEXEC code from the flash part.
This task is pulled into the build only when
the ROMEXEC relocation is installed.

08h

Initialize chipset registers to the Initial POST
Values.