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[SLUG] PC104 Ramdisk


I'm trying to get linux running on a PC104, booting from the on board
flash ram of roughly 4M.  This is in order to run a computer system on
board a supersonic rocket, see http://www.asri.org.au under small
sounding rocket program.

The difficulty is with "seeing" the flashram from linux. I'm confident
I could have the system boot a ram disk from DOS in the flashram, the
path being DOS - loadlin - vmlinuz - rescue.gz to ramdisk.

While I'd then have a running linux system, it would be nice to write
data to the flashram so it remains there after power down. If it could
be mounted as a dos disk, I'd then save a file to it, and all would be
well.

If you boot DOS, there's a "mystery" hard drive which appears as logical
disk 1 when you run DOS fdisk. It also appears when you boot a separate
DOS floppy.

But, if you boot linux, it does not see the flashram disk. This leads me
to suspect that the drive is accessed via BIOS, which is why linux does
not recognise the flashram disk and map it to /dev/hda(?1).

I'd have to build a specialty rescue image to use mdir and other mtools
functions, but I imagine they access the device nodes and would not
access BIOS. Tell me if I'm wrong.

Anyone know of DOS tools for linux which access the BIOS functions ?