[Coco] SuperIDE and floppy disk

Thu May 9 12:40:50 EDT 2013

well this is what is written on cloud-9 site:

http://www.frontiernet.net/~mmarlette/Cloud-9/Hardware/MPI%20PAL.html

On Thu, May 9, 2013 at 12:37 PM, Gene Heskett <gheskett at wdtv.com> wrote:

> On Thursday 09 May 2013 12:36:06 Luis Antoniosi (CoCoDemus) did opine:
>
> > ? PEEK(&HFF90) gives me 126.
> >
> $FF90 is NOT the MPI, $FF7F is its slot selection logic.
>
> > So the kit is there.
>
> Not by that data, you were looking at the GIME.
> >
> > On Thu, May 9, 2013 at 12:23 PM, Gene Heskett <gheskett at wdtv.com> wrote:
> > > On Thursday 09 May 2013 11:59:07 Retro Canada did opine:
> > > > i am using 51 and not $51
> > >
> > > Which translates to $33, or slot 4.  Exactly as if you had powered it
> > > up with the switch set to 4.
> > >
> > > The problem with coco3's and MPI's in that the coco3 writes to the
> > > GIME's memory mapping registers in the $FF90-$FF9F block.  But the
> > > address decoder in the MPI is as usual for tandy, very very
> > > incomplete, and those writes also get decoded to the MPI's slot
> > > select logic at $FF7F.
> > >
> > > The CoCo3 fix kits fix that, so a screen change on the coco3 doesn't
> > > muck with the MPI's slot select.
> > >
> > > > but i have fdc (4), superide (3), orch90(2) and s/sc on (1)
> > >
> > > Do you know for a fact that none of the above carts share an I/O
> > > address, which is normally done in in 4 byte wide pieces, the FDC
> > > being addressed at, depending on which register in the FDC chip is
> > > being addressed, $FF40 to $FF43, and the drive control logic is at
> > > $FF48.  But because of the defective address decoding, the FDC
> > > registers also appear at $FF50-FF53, and the drive control logic at
> > > $FF58.  Because of this, no other pack can have an address below
> > > $FF60.  That leaves IF the packs are fully decoded, room for only 7
> > > devices out of the whole menagerie of carts we actually have, many of
> > > which paid zero attention to staying within a 4 byte block for their
> > > address usage.  The WP-RS I have, had an unused gate in it that can
> > > be used to restrict it to one 4 byte wide block, but as OOTB, it uses
> > > the top two byte of the $FF64 block, and the bottom 2 bytes of the
> > > $FF68 block.
> > >
> > > I don't own a superide, or an orch90, and I haven't plugged in my s/sc
> > > in at least 15 years, so I have no idea where they are physically
> > > addressed.
> > >
> > > So I think you can see that you are dealing with a minefield, and the
> > > first thing you'll need to do is make sure that kit is installed in
> > > your MPI, and then adjust the address decoding, and the driver
> > > software both, if there are any addressing clashes in your setup.  It
> > > sure sounds like there is from here.
> > >
> > >
> > >
> > >
> > > Cheers, Gene
> > > --
> > >
> > > "There are four boxes to be used in defense of liberty:
> > >  soap, ballot, jury, and ammo. Please use in that order."
> > >
> > > -Ed Howdershelt (Author)
> > > My web page: <http://coyoteden.dyndns-free.com:85/gene> is up!
> > > My views
> > > <http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml>
> > > "Even more amazing was the realization that God has Internet access.
> > > I wonder if He has a full newsfeed?"
> > > (By Matt Welsh)
> > > A pen in the hand of this president is far more
> > > dangerous than 200 million guns in the hands of
> > >
> > >          law-abiding citizens.
> > >
> > > --
> > > Coco mailing list
> > > Coco at maltedmedia.com
> > > http://five.pairlist.net/mailman/listinfo/coco
>
>
> Cheers, Gene
> --
> "There are four boxes to be used in defense of liberty:
>  soap, ballot, jury, and ammo. Please use in that order."
> -Ed Howdershelt (Author)
> My web page: <http://coyoteden.dyndns-free.com:85/gene> is up!
> My views
> <http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml>
> In every non-trivial program there is at least one bug.
> A pen in the hand of this president is far more
> dangerous than 200 million guns in the hands of
>          law-abiding citizens.
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco
>

-- 
Long live the CoCo