Re: [hatari-devel] Regression in 2.0.0 RC1

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 27/10/2016 à 20:23, Christian Zietz a écrit :
> Nicolas Pomarède schrieb:
>
> > I wonder if the DMA sound doesn't output anything after a reset until
> > something is really written to dma start and/or end addresses ?
>
> Just a theory -- sadly, I don't own an STE to test this on the actual
> hardware. If both start and end addresses are initialized to 0, as you
> say, will the sound playback maybe stop instantly after being started,
> so that no (random) sound is being played? I suppose, with enough
> perseverance, one could deduce the actual behavior from the GSTMCU's
> schematics, which we have now: <http://www.chzsoft.de/asic-web/>

Hi

I know from another demo that if you set start=end, then sound will be 
played (I think dma first increases start by 1 word, then compare with 
end, so you will play the whole RAM if you do that, but it's possible).

Maybe there's a special case when start=end=0, or maybe there's so kind 
of "unitialized state" after a reset where we would read 0 for 
start/end, but the DMA would not start anyway ?

Hard to test without the real HW :)

Nicolas