Creating a Boot Floppy

To enable you to boot from a local device, a distribution from TimeSys includes the mkbootfloppy utility. Most x86 and IA-32 based embedded development boards use a BIOS that provides the same boot options as a standard x86 or IA-32 desktop system. These typically include the ability to boot from a number of physically attached local devices, rather than being able to boot over the network as do most embedded development boards using other types of processors.

The mkbootfloppy creates a floppy disk containing a bootable Linux kernel that is pre-configured to use DHCP to obtain and assign the board’s IP address, download a kernel from a remote host using TFTP, and identify the root filesystem you made available through NFS. The kernel then automatically mounts and uses this root filesystem during the boot process.

To create the boot floppy, use the following procedure:

  1. Insert a blank floppy disk into the floppy drive of the system on which you installed this Linux distribution. It is not necessary to mount the floppy disk drive.
  2. Use the cd command on the system where you installed this distribution to move to the following directory:
     cd <rfs_dir>/sbin
  3. Execute the command ./mkbootfloppy, being sure to include the “./” to ensure that you are executing the command in the current directory. The mkbootfloppy utility formats the floppy in /dev/fd0 and then copies a disk image to the disk:
    # ./mkbootfloppy
    This script will create a TimeSys Linux boot floppy.
    Note that the floppy will be formatted by this operation.
    Insert the floppy and hit Enter to continue or Control-C to abort:
    Double-sided, 80 tracks, 18 sec/track.
    Total capacity 1440 kB.
    Formatting ... done

    At the prompt, make sure the floppy disk is in the drive, and then press Enter to start formatting the disk. When the format is complete, the mkbootfloppy utility copies the boot image to the floppy disk. The command prompt returns after the image has been copied.

  4. Remove the disk from the drive and label it appropriately before continuing. You might want to write-protect the floppy disk to prevent its being accidentally overwritten.