Holds the current stack location (usually at address $0100 ). (Status Register) Stores flags: Carry, Zero, Negative, Overflow, etc..
Building a is a classic rite of passage for systems programmers. The MOS 6502 was the brain of iconic systems like the Apple II , Commodore 64 , and NES . Its simple architecture—featuring only 56 base instructions and 6 registers—makes it one of the best CPUs to emulate for learning purposes. 1. Architecture Basics 6502-emulator
The 6502 uses a 16-bit address bus, allowing it to address 64 KB of memory. Holds the current stack location (usually at address $0100 )