Hi folks!
The game I'm working on uses timer based interrupts quite heavily, but I noticed that my code produced significantly different timings between different emulators, upon further inspection, it seems like switching between an 8271 disk controller and a 1770 disk controller changes when my interrupts fire.
The 1770 causes the interrupt to occur about 8 pixel/1 character further down the screen (measured using a palette change), and I was wondering why this is? I imagine it won't be too difficult to fix once I know why, it just seems quite strange.
The game I'm working on uses timer based interrupts quite heavily, but I noticed that my code produced significantly different timings between different emulators, upon further inspection, it seems like switching between an 8271 disk controller and a 1770 disk controller changes when my interrupts fire.
The 1770 causes the interrupt to occur about 8 pixel/1 character further down the screen (measured using a palette change), and I was wondering why this is? I imagine it won't be too difficult to fix once I know why, it just seems quite strange.
Statistics: Posted by krool885 — Sun Jul 27, 2025 1:58 pm