Date   : Thu, 09 Sep 1999 20:02:46 +0100
From   : Iain Williamson <Iain@...>
Subject: Re: The full emulator

In message <19990909144010.27390.rocketmail@...>
          FARAZ CHOUDHRY <razzledazzler2@...> wrote:

> > You can use BBC Explorer to create a disk image from
> > a PC file:
> > http://www.nvg.ntnu.no/bbc/util/BBCExplorer-2.zip
> > Alternatively use my DISKMGR program included with
> > the full package.

> I would have thought that all BBC files are the same whichever it loads
> into, the real thing or the emulator.  Otherwise why is an emulator an
> emulator if it cannot load/save BBC files like the real thing?  Why the
> need for conversion to and from actual BBC file to PC BBC file?

Unless you're using a modern Acorn computer, the filesystem cannot hold
all the information that the Beeb one could (just as the beeb cannot
hold all the information that the PC can).

It's primarily a matter of load and exec addresses, which are very
important for beebs. Modern Acorn computers allow for this by having
either a date _or_ load/exec addresses for each file. Much PC software
would prolly get upset it it found un-dated files on your hard disc.

> > >Can the program read off PC disks as well as BBC
> > ones?
> > No, BBC disks are in a proprietary Acorn format, PC
> > disks use FAT.

> I suppose I would need to serial link a downloaded PC file into a Beeb
> then put into BBC disk, yeah?  Anyway, my friend has connected a 5.25"
> drive to a PC and I have PCBBC installed on his computer.  Now I hope
> to run some "raw" BBC programs on the emulator from my DFS formatted
> disks.  Isn't it as simple as that?

I believe the disc driver logic doesn't support the (relatively) low
densities that beeb discs use.

Serial link to the beeb is probably the best bet. I use a special user
port -> printer port link with !65link on my Acorn. I don't believe
there's anything equivalent on the PC. It gives a filesystem to the
beeb which actually lives on my main computer's HD, and is rather big.
And fast.

-- 
  /""\       Iain Williamson
 C  oo      Software engineer
 _(  ^)
/    ~\