Holds the current stack location (usually at address $0100 ). (Status Register) Stores flags: Carry, Zero, Negative, Overflow, etc..

Locations where the CPU looks for jump addresses when it resets or receives a signal. 2. The Emulation Loop The core of your emulator is a "Fetch-Decode-Execute" loop: Emulating a CPU in C++ (6502)

To start, you must define the data structures representing the CPU's internal state. Description (Program Counter) Points to the next instruction in memory. A (Accumulator) Used for all arithmetic and logic. X & Y (Index) Used for addressing offsets and loops. S (Stack Pointer)