FreeBSD  Release  11.0  Install  Guide



BIOS Update

There may be times when your PC BIOS may have a update provided by the vendor. To physical update the motherboard BOIS chip the PC has to be booted in MSDOS and then the vendor supplied flash program can be executed to apply the new bios.bin file to the motherboard BOIS chip. This was all fine and dandy when all PCs had floppy drives. But in todayís world PCs are not manufactured with floppy drivers any more and MS/XP and newer Windows systems have no option to create bootable MSDOS media. That leaves you with two options. Create a MSDOS bootable USB Stick or create a bootable CDROM. Both procedures are covered here.

Creating a bootable MSDOS USB stick (flash drive) is simple. But it has itís own set of problems depending on how old the PC is. Itís not un-common for PCís manufactured before 2008 to have BIOS that lack the option to boot from USB devices or even fail to recognize USB media as bootable.

First thing is to determine if your current bios have the option to boot from USB devices. During power on enter BIOS setup menu and check the boot device order for option to boot from USB. If itís absent a MSDOS bootable USB Stick wonít work for you.

If your PC BIOS has the option to boot from USB, then configure the first boot device to be from USB and the second from cdrom and the third from the hard drive. If at boot time there is no bootable USB device plugged in and no bootable CD in the CDROM/DVD drive then you will default to booting from the motherboard cabled hard drive.

The following steps are common to creating both the MSDOS bootable USB Stick and the bootable CDROM.

There are three files you have to acquire before starting this process.

1. A bootable floppy image. Download the floppy.img from floppy.img.z Once you have it downloaded, rename it removing the .z suffix. In this case the floppy image contains the basic programs to fix any fat32 drive, IE. [fdisk, format, scandisk, edit, chkdsk, more, find,,, io.sys, msdos.sys] files and was created using Windows 98.

2. The MS/DOS flash.exe utility provided by the BIOS vender used to update the BIOS chip.

3. The vender supplied bios.bin file used to write over the old PC BIOS chipís content.

Warning: Using the wrong flash utility or wrong update bios.bin file can result in irreversible damage to your motherboard BIOS chip making your motherboard unusable.

Make a memory disk of the floppy.img so you can access its contents.

mdconfig -f /path/floppy.img
mount_msdosfs /dev/md0 /mnt
cd /mnt

Now you see all the files in the floppy.img. To this you have to add the 2 vendor supplied files used to update your motherboard BIOS chip.

cp /path/flash.exe /mnt/
cp /path/
bios.bin /mnt

You see your BIOS update files are added into the floppy image.
Now free the floppy.img.

cd /
umount /mnt
mdconfig -d -u md0

This is the end of the common stuff.

Only do this if creating MSDOS bootable USB Stick
Write the floppy.img to the USB stick

dd if=/path/floppy.img of=/dev/da0

The creating of your MSDOS bootable USB Stick is now finished.

The following steps are unique to creating the bootable CDROM.

Now your ready to create the cd.iso file. You will need the mkisofs command. It's not part of the base system so you have to install it from the ports system or package system.

pkg_add -r cdrtools
mkisofs -J -R -b /path/floppy.img -o /path/cd.iso /path/floppy.img

Now your ready to burn the cd.iso file to CDROM. The burncd program is part of the base system. If youíre using a cd/rw CD and it all ready has data on it then blank it out.

burncd -v -f /dev/acd0 -s4 -e blank fixate

Ready to burn your bootable cd.iso to cd

burncd -v -f /dev/acd0 -s4 -e data /path/cd.iso fixate

Before powering on the PC thatís to have itís BIOS updated plug in the USB stick you just created or load the bootable CD you just created in itís drive. The boot is very quick and displays the MSDOS command line as drive A:
To display the contents of drive A: issue


Then key in the program to update the system BIOS chip and
follow the vendors instructions.


When completed, remove the USB stick or CD and reboot the PC. If your PC doesnít boot then you know you have a very big problem. The BIOS update you just ran didnít work or the update bios.bin file was not the correct one for your bios chip. Your only remaining option is to buy a new motherboard from a know vendor who provides technical support for their equipment.

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