Re: [ECOS] load data from floppy

[davidw at dedasys dot com (David N. Welton)]

Nick Garnett <nickg@ecoscentric.com> writes:

> 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.

As part of the kernel?  The ideal result would be to create a system
in which the jpegs are attached later rather than at compile time...

I'm having a go at making a floppy driver, but it doesn't appear to be
particularly simple:-/

Thankyou for your time,
-- 
David N. Welton
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