[Coco] Instruction cycles per 60Hz frame.

James Ross jrosslist at outlook.com
Sun Nov 17 21:16:02 EST 2019


Thanks for the answers, Ed, Evan & Will --> I believe those answers clear it up and give me the most precise / accurate #'s possible.  

Bottom line then: we have 

14,929 cycles in normal speed (15 more than I had calculated) and
29,859 cycles in double speed (30 more than I had calculated).

So, for a game attempting to update the screen at 60hz this is what you have to play with – which isn’t all that much specially when you consider we have no blitter, no sprites.  and no sound chip for that matter… (the CoCo was truly handicapped, but I never thought it that way back in the day!) 

Also an emulator needs to take into account the 59.94Hz vs 60hz discrepancy for the best accuracy. 

James


More information about the Coco mailing list