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From: dvljrt@cs.umu.se (Joakim Rosqvist)
Newsgroups: comp.sys.amiga.programmer
Subject: Re: playing samples using audio h/w
Keywords: audio DMA
Message-ID: <1991Mar25.001553.10872@cs.umu.se>
Date: 25 Mar 91 00:15:53 GMT
References: <2325@m1.cs.man.ac.uk>
Sender: news@cs.umu.se (News Administrator)
Organization: Dep. of Info.Proc, Umea Univ., Sweden
Lines: 22

In article <2325@m1.cs.man.ac.uk> snowdond@r2.cs.man.ac.uk (D.N.Snowdon (MSc PJ)) writes:
>
>  I'm having a problem playing sound samples by hitting the
>hardware directly. The problem is that I set up the registers
>for the channel I'm going to use and set audio DMA going
> using 
>   move.w #(DMAF_SETCLR!DMAF_MASTER!DMAF_AUD0),dmacon(a0)
>as per the h/w manual. The sound starts playing OK.
>  If I then stop the sound by turning its DMA off using
>  move.w #DMAF_AUD0,dmacon(a0) again as in the h/w manual, 
>the sound stops. If I then reload the registers and start
>DMA going the sound I get is the remains of the first sample
>(assuming I stopped it before it had finished playing
>completely). The h/w manual does say that if you stop and
>start DMA over a short period then this can happen but there
>is actually quite a long delay between turning off DMA for
>the first sample and turning it on for the second.

How long is 'quite long'? The sound will only replay from where you stopped it
if the next 2 samples has not been read from memory yet.
Could you send the relevant part of the code, perhaps there is some simple
error?    /$DR.HEX$