Re: Filesystem creation

[Dan Olson <dano@agora.rdrop.com>]

> The problem with your quote above is quite a simple one - the original
> IBM PC didn't scan for adapter BIOSes, so was VERY limited in what
> expansion one could add to it. That was an oversight by IBM's engineers
> as they provided the slots for plugging in expansion cards, but forgot
> to allow for BIOS support for those expansions. The BIOS included the
> ability to boot from floppies as standard, but that was about all.
>
> This was the original version of the original IBM PC, with a fixed 16k
> of RAM that couldn't be expanded on the motherboard.

Ah! Okay, I've never seen such a machine, they were very short-lived.
Maybe someday I'll find one.

> This is the one I mis-labelled - this is the revised original PC, where
> the RAM could be expanded from the supplied 16k up to 64k, and NOT the
> PC/XT as I originally labelled it. Yes, I had one, and I paid the extra
> for the floppy drive.

Okay, that makes sence now, the floppy was definetly an option in those
machines.

> This is where Bill Gates made his famous "Nobody will want more than
> 64k" comment - see below for his later comment.

I forget the exact story, but I think he's the one who pushed IBM into
making the PC a 64-256k machine, as the original 16k was too limiting.  Of
course sticking adaptor ROMs at the 640k-1M range was done because 640K
was way more memory than anybody could use! :)

>    3a. The "revised IBM PC/XT" was the original IBM PC/XT with the
>        onboard RAM capacity upgraded to 640k when the clones were all
>        offering 512k on the motherboard. The clones promptly followed
>        and allowed 640k as well.

Okay, that's what my board is, I was wondering if it was a true IBM
offering as all the documentation I have mentions the board having a
smaller capacity.  Turns out there's a jumper on the board that selects
which type of system you have...ie it determines the amount of memory the
DIP switch settings give you.

> > And it ran at a whopping 6MHz too :)
>
> Exactly the same as the PC/XT-286 that preceded it. I liked the "standard
> extras" phraseology myself...

That's great...then again, they were probably impressive compaired to some
of the other clones of the day, with the 16 bit ISA bus and all.

> > Well, it's not handy, but I still have it. If I stumble across it I'll
> > grab it and see if it works or not. I'm having a hard enough time just
> > getting a boot disk made and installed in my IBM XT (eXtended Technology :).
>
> Could you advise what the problem is with doing that? The various Linux
> distributions all supply rawrite.exe which can write the image out to
> floppy under MS-DOS so the procedure isn't hard.

I guess that wasn't too clear, it hard simply because I'm always doing
something else, it would be much easier if I took an hour and sat down in
front of the computer and made the disk, then gave it a try.  It's also
hard because I'm sharing one desk/monitor between three PCs :)

> We would all love that. However, according to Alan Cox, BCC is slightly
> too large and as a result won't compile itself, although the assembler
> and linker both compile fine to run under ELKS.
>
> There's one or two tweaks I would like to see done to BCC anyway, so I
> may soon be looking into this and seeing if I can get bcc to compile
> itself. No promises though...

Well, compiling itself is definetly a good thing, but even if we could
compile a binary on a different machine, then stick it on an ELKS disk
image or something, that'd be all I'd want.  I'm just interested in
writing a couple short programs on the ELKS machine, then compiling them
locally.  Is that a difficult task?  I have no idea what it'd take to get
a compiler running under ELKS.

	Dan