BIOS update w/o floppy drive

Some newer notebooks come without a floppy drive. Nonetheless, one needs to update the BIOS. Sometimes, notebook manufacturers provide special BIOS update executables for Windows which bypass the DOS floppy based BIOS update mechanism. Now, the problem arises for those people who don't run Windows and don't have a floppy drive.
This step by step approach illustrates how to update your BIOS on a Compaq Evo N800v without having to run Windows or depending on floppy drive.

Step by step

1. Get the BIOS update file
   The Driver Page for the Evo N800v lists a ROMpaq file which contains the DOS BIOS update executable. Download that file.
   
   
2. Extract the DOS BIOS executable file
   

   wine SP25814.exe

   It will eventually show a message discopy 68MP4.IMG A: where you can cancel the program as the executable is extracted and we don't want to wait for the program to search for the floppy drive.
   The file is extracted to the folder ~/.wine/fake_windows/SWSetup/sp25814/
   
   
3. Go to the BIOS image folder
   

   cd ~/.wine/fake_windows/SWSetup/sp25814/

   You should find the following files within that directory:

   68P4M.IMG SP25814.txt COPYDISK.EXE WSSP25814.txt copydisk.bat

   
   
4. Convert the floppy disc image
   Unfortunately, the 68P4M.IMG is a special COPYDISK.EXE image. You can look at the first few bytes of this image and see the COPYDISK Name yourself. A real floppy is 1.44MB or 1474560 Bytes in size. The 68P4M.IMG ist 1474592 Bytes, so 32Bytes more. It looks like the first 32Bytes are just COPYDISK image headers. So lets extract the real image.

   dd if=68P4M.IMG of=image skip=1 bs=32

   
   
5. Create an El Torino ISO
   We will now use the real image to make a bootable CD.

   mkdir boot
   mv image boot/
   mkisofs -b boot/image -c boot/boot.catalog -o evoupdate.iso .

   
   
6. Burn the ISO file
   

   cdrecord dev=0,0,0 -v evoupdate.iso

   You can now use the bootable CD to update your BIOS.
   
   

Final Note

The ISO files contains some files more than we actually need but I left the steps out to remove them for simplicity.
Hint: you would only need the boot directory content on the CD.