Key questions to consider based on page 10 of this document:
- What does page 10 imply by "Add 1 to N if page boundary is crossed"?
- What does page 10 imply "Add 1 to N if branch occurs on the same page?"
- What does it mean by add 2 to N if branch occurs to different page?
- Does read and write to other devices ie.RAM cause any irregularities in clock cycles?
- Are there any other factors that could affect clock cycles on the 6502 (more specifically the NES) ?