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It's been quite a while since i have programmed. i've made the code for the states as data. It doesn't work right. The little ship flashes around a little and then vanishes.

i remember debugging using a variable "look" located on the zero page close to $0000. I would place "sta look" after a crucial line of code and then run nintendulator, pause it and see what value look contained.

Now, i cant figure out how that works with debugging. How do you know when to pause nintendulator? i have forgotten how to debug. Could you please help refresh my memory a little?

You set a watch on writes to 'look'. How to find where 'look' has been placed in RAM depends on your assembler (see if it can output a "symbol table"); how to set the watch depends on your emulator.

How do you set a watch in nintendulaor? i know that look is in spot #0006 because it's the 7th variable in the zero page variable list. i can check its value in nintendulators disassembly screen. Is that a watch? (i've never heard of doing a watch before.)

Nintendulator does not support "watches" (memory I/O breakpoints), only address execution breakpoints. If you want to watch for a memory write, you'll have to use a different emulator for that.

1.) What is a a "watch"?

2.) What is a good emulator that supports "watches"?