Post #3694683

so issuing an "illegal" opcode on the game boy cpu essentially shuts the cpu down (illegal opcodes don't set the fetch flag, so the pc won't increment—and the cpu only services interrupts at the beginning of a fetch). BUT all the other peripherals on the SoC keep running! i feel like between the PPU, APU, timers, DMA, etc. there MUST be a way to "program" the game boy to do something even when the cpu is in illegal opcode zombie mode. this has no practical purpose of course but—food for thought!