Setting Up the BIOS Boot Loader

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Two floppy disk images are provided in Platform Builder, Setupdisk.144 and Bootdisk.144. Setupdisk.144 is a MS-DOS FAT-formatted floppy disk that contains disk setup utilities and the boot sector and boot loader images. Bootdisk.144 is a sample boot disk for downloading an OS image from Platform Builder that demonstrates the BIOS boot loader and uses Eboot.bin.

To use the floppy disk images

  1. If Websetup is not already installed on your system, install it by running Websetup.exe from <Platform Builder installation path>\Cepb\Utilities on your development workstation. Websetup only needs to be installed once.

  2. Place a floppy disk in your floppy drive.

  3. Run either Setupdisk.144 or Bootdisk.144, which is located at %_WINCEROOT%\Public\Common\Oak\Csp\i486\Biosloader\Diskimages. The .144 file extension is associated with Websetup.

  4. Select the A Drive button and the floppy disk will be prepared.

    Use the setup floppy disk, Setupdisk.144, to prepare a storage device with the BIOS boot loader.

    Note   This step assumes that the storage device to be prepared is in an x86 system with a floppy drive and where the storage device is visible to MS-DOS as a drive.

To prepare the storage device

  1. Insert the setup floppy disk and boot it.

  2. From the command prompt, use the fdisk utility to create a primary MS-DOS active partition on the storage device. Since the BIOS boot loader does not currently support FAT32, create a partition whose size is FAT12 or FAT16 compatible. For more information about how to use fdisk, consult the fdisk documentation.

    Note   You should prepare the disk in the target device. If you cannot do this, ensure that the BIOS settings for the drive, such as the LBA mode and others, match the settings used on the target platform. On-disk settings are stored as part of the fdisk operation and must be compatible with the working BIOS mode.

  3. From the command prompt, format the new partition using the format utility.

    Note   The MS-DOS system files should not be transferred as part of the formatting process. Specifically, do not use format /s <drive>. When prompted by the format utility, leave the volume name blank.

  4. Use the mkdisk batch file to write the boot sector image and to transfer the boot loader. To use this batch file, you should type mkdisk <drive letter>. For example, if you are using the C: drive, you would type mkdisk c:.

At this point, the storage device contains an active partition that is bootable and contains both the boot sector and boot loader images. The mkdisk utility sets the attributes of the BIOS loader image (BLDR) to hide or protect the file. Listing all the files in the root directory of the storage device will not show any files.

Once the storage device is prepared with the BIOS loader, the BIN image to be booted needs to be transferred to the root directory. By default, the BIOS boot loader looks for a file in the root directory called Nk.bin, which is the OS image. Because the storage device contains a standard FAT file system, if the storage device is removable, it can be placed in any desktop system and the boot image can be copied to the root directory on the storage device.

When the BIOS loader boots, it sends information over physical COM1 on the target device. If you run into problems booting an image with the BIOS loader, connect a Hyperterm connection, 38400 N81, to COM1 for more information.

See Also

x86 BIOS Boot Loader

Last updated on Wednesday, April 13, 2005

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