[hatari-devel] Chaos AD problem : $fffffc02

[Laurent Sallafranque]

This demo uses 3 sound buffers

The problem is somewhere else.

Regards

Laurent


Le 13/06/2011 23:50, Nicolas Pomarède a écrit :
> Le 13/06/2011 23:37, Laurent Sallafranque a écrit :
>> I've checked the DSP part. Nothing special at first glance.
>>
>> I'll check it more.
>>
>> I think many sound problems may come from the fact that the real Falcon
>> DMA sound has 2
>> 32 bytes buffers.
>>
>> I've already thought about coding them in the crossbar, but I need some
>> infos
>>
>> - when are these buffers filled by the Falcon ? (at VBL, every xxx
>> cycles, ...)
>> - Is there a "burst mode" like in the videl DMA ?
>>
>> I may try to read a few bytes every HBL, as Nicolas did for the STe and
>> see if this increase the sound quality.
>> (after 1.5)
>>
>> Regards
>>
>> Laurent
>
> Hello
>
> before doing that, you should check that the demos with bad sound are 
> really writing in the same buffer that is being played.
>
> If this is not the case (if the replay really uses double buffer), 
> then the problem is certainly not related to an internal sound buffer 
> or the need to update every HBL.
>
> So, demo replays should be studied first to see if they use double 
> buffer or not (easy to see : just check if sound start/end address is 
> the same on every VBL or not) ; this first analysis is necessary to 
> avoid spending time in some modifications that in the end might not 
> improve anything.
>
>
> Nicolas
>