blastar (./63) :

NeoHomeBrew (./62) :
..hopefully the frame-rate of my code is not to slow for it

do you ever tried the auto-anim-flag in SCB1?maybe you can use this, it's code-independent.

Yup this is right, it does not matter if your game is even 10fps, the anim will always be 60fps on NTSC systems, 50fps on PAL. Its a win win for transparent effect using cycling checkerboard and i'm surprised more neogeo games never used it. Im guessing you have though about some ways to abuse this feature blaster