One embodiment is a method of detecting BIOS corruption that does not
require reprogramming of the boot block or calculation of cyclic
redundancy ("CRC") codes. A simple check is performed using only the first
byte or bytes of BIOS to be erased ("First Byte") and the last byte or
bytes of BIOS to be programmed ("Last Byte") during reprogramming.
Specifically, if both the First and Last Bytes are programmed, indicating
either that erasure did not occur or that reprogramming was successful,
the BIOS is not corrupt and no remedial action need be taken. If the First
Byte is erased and the Last Byte is programmed, indicating that a failure
occurred during erasure, the BIOS is corrupt and remedial action must be
taken. Similarly, if the First Byte is programmed and the Last Byte is
erased, indicating that a failure occurred during reprogramming, the BIOS
is corrupt and remedial action must be taken. Finally, if both the First
and Last Bytes are erased, the BIOS is corrupt and remedial action must be
taken.
