Phantasy Star collection graphical glitches

[benderscruffy]

during the game the text shows twice on the screen

[Hydr8gon]

Could you post a screenshot?

[benderscruffy]

here is a screenshot

[fleroviux]

Like #20 this game also relies on open bus during DMA transfers. You'll have to handle regular open bus reads from unused MMIO addresses. The game will first transfer one value from ROM to a vertical scrolling register. Immediately after that it will transfer one value from that scrolling register to another vertical scrolling register. Since scrolling registers are write-only this only works out due to open bus.