Re: [ECOS] load data from floppy

[Nick Garnett <nickg at ecoscentric dot com>]

davidw@dedasys.com (David N. Welton) writes:

> Exactly what sort of messing about would be needed?  Some sort of
> floppy driver?  How does GRUB manage it?:-) A cursory glance at the
> code seems to indicate that they have a generic, layered system in
> place.  A little bit more complex for those like me who don't grok PC
> hardware at the expert level.

To load stuff above the 1M mark needs the code to read sectors in to
the bottom 640k and then copy them out to their eventual home using a
BIOS mechanism. The loader then needs to switch to protected mode and
jump to the executable. To do this we would have to rewrite the loader
code, and change the way it links to the eCos executable. It's much
easier to do this with a loader that already handled it, like GRUB.

> No, the article is really just an introduction to eCos.  I was
> thinking along the lines of showing how it's smaller than Linux by
> squeezing a bunch of stuff (jpegs, in this case) onto a floppy.

In which case these jpegs could just be loaded as binary data by GRUB
when it loads the executable.

-- 
Nick Garnett                    eCos Kernel Architect
http://www.ecoscentric.com/     The eCos and RedBoot experts


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