[Coco] 8 slot multi pak

[Michael Brant]

Vincent?  you going to tell Ed to not build a 100 slot MPI or am I?  Surely
Ed, could not ever come up with a PCB for that?

On Tue, Jan 17, 2017 at 3:28 PM, Mathieu Chouinard <chouimat at gmail.com>
wrote:

> why just stop a 16 ;)
>
> On Tue, Jan 17, 2017 at 3:19 PM, Brian Blake <random.rodder at gmail.com>
> wrote:
> > Ed... I triple-dog dare you to make one...
> >
> > On Jan 17, 2017 2:46 PM, "Zippster" <zippster278 at gmail.com> wrote:
> >
> >> There’s an issue with going beyond 4 slots on an MPI, software support.
> >>
> >> The arbitration scheme using *CTS and *SCS traditionally only supports
> >> for slots, so old software that uses these signals for selecting carts
> >> would mean
> >> you’d only be able to use the first four slots and stay compatible.
> >>
> >> Also, the *CART interrupt goes to the slot receiving *CTS, so autostart
> >> carts
> >> would be limited to the first four slots as well unless the arbitration
> >> scheme is
> >> extended.
> >>
> >> Now some things don’t use those signals, like the DACs on the Orch90,
> and
> >> items
> >> like that could go into extended slots without changing old software.
> >>
> >> A thought that occurs to me is that with the unused bits in the MPI
> >> register at $FF7F,
> >> the use of the *CTS/*SCS scheme can be easily extended to as many as 16
> >> slots.
> >> In fact, it looks like the bit locations might have been chosen with
> this
> >> in mind.
> >>
> >> New software could easily support this, and perhaps old software can be
> >> patched,
> >> though at some point additional bus buffering may be needed.
> >>
> >> Thinking about it more, maybe this isn’t much of an issue.  You’d just
> >> have to choose
> >> what slots you use which carts in carefully depending on the software
> >> you’re using.
> >>
> >> Someone please tell me not to make a 16 slot monstrosity just to make
> use
> >> of those
> >> register bits….   lol…  :)
> >>
> >> - Ed
> >>
> >>
> >>
> >> > On Jan 17, 2017, at 12:47 PM, Michael Brant <
> brant.michael.l at gmail.com>
> >> wrote:
> >> >
> >> > Jim, it was my understanding is that you were building the mpi with
> the
> >> > capability for 8 slots via 2 banks of 4.
> >> >
> >> > On Jan 17, 2017 1:39 PM, "RETRO Innovations" <go4retro at go4retro.com>
> >> wrote:
> >> >
> >> >> On 1/16/2017 10:40 PM, Brian Goers wrote:
> >> >>
> >> >>> What is the status of the 8 slot Multi pak.
> >> >>> How is the testing going?
> >> >>>
> >> >>>
> >> >> I am finishing the final PCB design to the 4 port unit (with some
> relays
> >> >> for power), but I am not aware of any 8 port testing.
> >> >>
> >> >>
> >> >> Jim
> >> >>
> >> >>
> >>
> >>
> >> --
> >> Coco mailing list
> >> Coco at maltedmedia.com
> >> https://pairlist5.pair.net/mailman/listinfo/coco
> >>
> >
> > --
> > Coco mailing list
> > Coco at maltedmedia.com
> > https://pairlist5.pair.net/mailman/listinfo/coco
>
>
>
> --
> A te quaeso, sicut in Aeneidos libro quarto Aeneas, elocutus
> desiderium erigendi suum obeliscum in templo Venereo Didonis, ab ea
> quaesivit, tuae domi an meae?
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> https://pairlist5.pair.net/mailman/listinfo/coco
>