Initialize FLASH to 0xFF for each byte
Improve frame event sequence

Not sure if it’s correct
Improve inline ASM in graphics

Better way to clear the registers, using fewer instructions when
comparing with mask
Fix a problem with background layer transforms

Basically, the hardware doesn’t actually apply it as a matrix
multiplied by a vector, it actually uses increments on each line and
pixel. This is a problem when the reference point registers are changed
mid frame, because it effectively resets the incrementation, which is
used by game like mario cart.