Re: Recode to Play MP3?

["Michael J. Mahon" <mjmahon@aol.com>]

georg.bieling@gmail.com wrote:
> On May 23, 3:23 pm, mdj <mdj....@gmail.com> wrote:
>
> > Since the Zips cache is write-
> > through, it seems like an oversight that they didn't simply flag the
> > cache lines as invalid when DMA was activated.
>
>
> Probably that's because it's not so easy to tell from the 6502 socket
> that the /DMA line is being pulled low.
>
>
> > In the case of the Transwarp I, it actually *is* a DMA peripheral.
>
>
> But the DMA daisy chain supossedly serves the purpose of arbitrating
> peripheral cards' DMA requests...
> Isn't the transwarp I a well-behaved DMAer, then ?
> Or is it that the DMA daisy chain mechanism fails short in
> accomplishing it's intended purpose ?

It often does, since the daisy chain is often broken by absent or
non-loop-through cards.

DMA on the Apple II is a dicy business.

-michael

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