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Re: Mix LGR and Text?

Jorge Chamorro Bieling wrote:

Joseph,

You're right, now I believe I understand: after finding (vsync or
whatever) by polling, you can be sure that you can use (whatever the
amount) of cycles before the next (vsync or whatever) arrives, so as
long as you don't exceed this number of cycles you'll be still in time
to lock to the next (vsync or whatever)...

You have to split your code in chunks of no-more-than whatever cycles.


Actually, once you achieve lock, you never look at VBL or the
vapor lock bytes again.  You just count cycles perfectly, and
the processor stays in exact sync with the video generator.

It would be possible to re-sync, but if you were more than one
cycle out of sync, it would take more than one field to
re-establish precise sync.

-michael

Music synthesis for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

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