Optimization was breaking some code :-( Will investigate later
Switching to state-machine-like code using state variable and function pointers.

Not quite as fast as a switch statement, but much cleaner.

'Compute' image during blanking period.

Draw image in main loop, instead of interrupts (much faster) Can draw around 200 horizontal lines at the moment. Can probably optimize that more later.

Changed #define's for SET_BLACK, SET_WHITE, etc... Instead of using FIOSET and FIOCLR, change the pins directly. This way, both change at the same time. This reduces overshoot significantly