[stella] Relationship of # of scanlines to framerate

[seagtgruff at aol.com]

The simplified versions of the two formulas are as follows:

NTSC Atari framerate = 3281250 / 209 / scanlines

PAL Atari framerate = 3546895 / 228 / scanlines

Michael


-----Original Message-----
From: Stephen Anthony <sa666666 at gmail.com>
To: Atari 2600 programming list <stella at atari2600.org>
Sent: Mon, 19 May 2008 2:01 pm
Subject: [stella] Relationship of # of scanlines to framerate



Can anyone point me to documentation on how the above is determined?  
Specifically, I know NTSC/262 is 60Hz and PAL/312 is 50Hz.  However, 
what 'formula' is used to determine this?  Put another way, if the 
scanline count was say, 280, what formula would I use to determine the 
framerate?

Thanks,
Steve

_______________________________________________
Stella mailing list
Stella at atari2600.org
http://atari2600.org/mailman/listinfo/stella

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://atari2600.org/pipermail/stella/attachments/20080519/f51c7fbb/attachment.html