Hardware Reference
In-Depth Information
then rename the image file to AMIBOOT.ROM. Power off the system to be recovered,
insert the floppy, and then power on; the recovery process should start automatically.
Most Phoenix and Award BIOSs also have a boot block with recovery capabilities. These
are designed to automatically boot from a floppy disk if the main BIOS is damaged. To
perform a recovery, first download the latest BIOS upgrade files for the motherboard. Ex-
tract the files and copy the Award flash program (awdflash.exe) and the correct BIOS im-
age (*.bin) file to a bootable formatted floppy, and then create an AUTOEXEC.BAT file
on the floppy with the command
awdflash.exe *.bin
, replacing the
*.bin
with the actu-
al name of the BIOS image file for the specific motherboard being recovered. Power off
the system to be recovered, insert the floppy, and then power on. The system should boot
from the floppy, and the recovery process should start automatically.
Withanyoftheseprocedures,waitatleastseveralminutesafteralldiskandbeepingactiv-
ity stops before removing the floppy or CD and restarting the system. When you power
the system back on, the new BIOS should be installed and functional. If nothing at all
happens,therecoverymayhavefailed,ortheboardmaynotfeatureaseparateboot-block
section (which contains the recovery code).
Note
Note that the BIOS recovery procedure is often the fastest way to update a large number of
machines, especially if you are performing other upgrades at the same time, or the machines
are new and do not have a bootable OS installed. For example, this is how updates are some-
times done in a system assembly or production environment.
Motherboard CMOS RAM Addresses
In the original IBM AT system, a Motorola 146818 chip was used as the real-time clock
(RTC) and CMOS RAM chip. This special chip had a simple digital clock that used 14
bytes of RAM and an additional 50 more bytes of leftover RAM in which you could store
anything you wanted. The designers of the IBM AT used these extra 50 bytes to store the
system configuration.
Modern PC systems don't use the Motorola chip; instead, they incorporate the functions
of this chip into the motherboard chipset (South Bridge) or Super I/O chip, or they use
a special battery and NVRAM module from companies such as Dallas Semiconductor or
Benchmarq.
Table 5.1
shows the standard format of the information stored in the 64-byte standard
CMOS RAM module. This information controls the configuration of the system and is
read and written by the system setup program.
Table 5.1 CMOS RAM Addresses
