[hatari-devel] Little question about SteDMA sound

[npomarede at corp.free.fr]

On Sat, 19 Sep 2009, Laurent Sallafranque wrote:

> Shouldn't we use the same value as Nicolas used in int.c instead ?
> As least, it would be the same value everywhere.
>
> I agree that the 8447 is not changing many things in the result, it's
> just to use the same value everywhere.
>
> Could this value be written as a define in configuration.h (at least, if
> we want to change it, it would be changed in Dmasnd.c too) ?
>
> regards
>
> Laurent

I don't know, this is hard to decide because :
  - it's absolutly sure that a VBL in 50 Hz is 160256 cycles
  - so 50 * 160256 should give the CPU freq, which is not the case in int.c

-> this could mean that the VBL is not exactly 50 Hz, but there's a small 
variation to adjust to the CPU freq to 8021247 Hz.

I think we should use 160256 * 50 everywhere, except in int.c as I don't 
have any mean to measure precisely the cpu freq and some slight variation 
there could mess with some programs requiring very precise mfp/cpu sync.

Nicolas

kk