GregM@cup.portal.com (Greg Scott Miller) (04/26/89)
I'm working on some general-purpose assembly audio code, and read awhile back that the primary audio frequency (1/3579545) is different for PAL systems. (I should have realized this, but it never occurred to me.) Does anyone have any idea how I can: (1) Find out whether my code is running on a PAL system or not. (2) Find the audio constant for PAL systems. Ideas, anyone? - Greg GregM@cup.portal.com
adam@cbmvax.UUCP (Adam Levin CATS) (04/27/89)
The NTSC clock constant is 3.579545.
The PAL clock constant is 3.546895.
To determine video format (PAL/NTSC) at runtime:
#include <graphics/gfxbase.h>
struct GfxBase *GfxBase;
GfxBase = (struct GfxBase *) OpenLibrary("graphics.library", 0L);
if ( GfxBase == NULL) /* Couldn't open library; clean up and exit. */
if (GfxBase->DisplayFlags & PAL) /* PAL machine. */
else /* NTSC machine. */
--
Adam Keith Levin -- CATS Commodore-Amiga Technical Support
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