Date   : Sat, 12 Jun 2004 13:11:01 +0100
From   : Sprow <info@...>
Subject: Re: Solid state storage for the beeb

In article <10406102022.ZM25888@...>,
   Pete Turnbull <pete@...> wrote:
> On Jun 10, 15:23, John Kortink wrote:
> >
> > GoMMC, as I've nicknamed the project, provides for
> > 'floppies on a flash ROM card'. Currently, a patched
> > DNFS 1.20 ROM provides, via a 8271 emulation layer,
> > 100% DFS-compatible access to 400K 'floppies' (about
> > 600 of them !) stored on a 256 MB Multimedia Card
> > (one of those tiny cards you usually put in a digital
> > camera, the 256MB ones are about 60 Euro/40 UKP ATM).
>
> At £35 or so, I'd be interested.  Will it work with lower-capacity
> cards (fewer "floppies"!)?  I have one or two "spare" 16MB ones.

What would be really great would be a 1770 emulation layer, then with
support to spot the DOS partition table, and my DOSFS. This way it could
also be used for transferring lumps of data from the PC (well, via my
digital camera and a USB cable actually) in edition to every floppy disc I
ever had.

I must say I'd be a little surprised if you can get 64kB/s over what is
effectively a synchronous serial link, the 24bBC RAM disc musters about
20kB/s using the 1MHz bus with a really tight loop - if the beeb is running
about 0.5MIPS then you'd have to be slurping one byte every 8 instructions.

Perhaps a few words about the hardware John? Maybe *it's* doing all the hard
work and the beeb just polls a location or sits on the NMI line doing page
long bursts?

Either way, well done John! Sounds like I can scratch that project off my
'to do' list, and JGH was looking at the IDE interface I think, so maybe I
should get a move on with the 14MHz TurboB I've been thinking about...
Sprow.