Bootblock Recovery Code Checkpoints - Acer G310 - Altos Service Manual

Bootblock Recovery Code Checkpoints

The bootblock recovery code gets control when the BIOS determines that a BIOS recovery needs to
occur because the user has forced the update or the BIOS checksum is corrupt. The following table
describle the type of checkpoints that may occur during the Bootblock recovery portion of the BIOS.
Checkpoint
E0
E9
EA
EB
EF
E9 or EA
F0
F1
F2
F3
F5
FA
FB
F4
FC
FD
FF
Chapter 4
Initialize the floppy controller in the super I/O. Some interrupt vectors are
initialized. DMA controller is initialized 8259 interrupt controller is initialized.
L1 cache is enabled.
Set up floppy controller and data. Attempt to read from floppy.
Enable ATAPI hardware. Attempt to read from ARMD and ATAPI CDROM.
Disable ATAPI hardware. Jump back to checkpoint E9.
Read error occured on media. Jump back to checkpoint EB.
Determine informatoin about root directory of recovery media.
Search for pre-defined recovery file name in root directory.
Recovery file not found.
Start reading FAT table and analyze FAT to find the clusters occupied by the
recovery file.
Start reading the recovery file cluster by cluster.
Disable L1 cache.
Check the validity of the recovery file configuration to the current configuration
of the flash part.
Make flash write enable through chipset and OEM specific method. Detect
proper flash part. Verify that the found flash part size equals the recovery file
size.
The recovery file size does not equal the found flash part size.
Erase the flash part.
Program the flash part.
The flash has been updated successfully. Make flash write disabled. Disable
ATAPI hardware. Restore CPUID value back into register. Give control to F000
ROM at F000:FFF0h
Description
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