I was playing a round after splitting the menu into 2 ROM banks to make room for extra graphics and the game reset to the main menu with all the options initialized to the power-up values. It doesn't happen all the time. I just check the version from 10-14 and it did the same thing. Anybody notice this on a version prior to 10-14?
The IRQ vector points to the same place the RESET vector does, so I suspect a BRK is being hit. I haven't coded a BRK, so this would imply data is being treated like program code. I checked the compile results for a branch-out-of-range and there isn't one.
I've added a RTI and changed the IRQ vector to point to it and have told Stella to trap if it hits the RTI. Hasn't happened yet.