fungus:
PetriH:
There is hardly any cycles left during screen refresh.Are there any left at all? Surely at some point it's better to just take over completely. The cycles spent responding to interrupts and saving/restoring state could be used for audio mixing, etc.
Yes, I have thought about this idea, to output the video signal directly without interrupts. But then everything has to be timed to the video signal and it becomes a huge PITA. I agree that to get the last few cycles out of the MCU it's the only way...