WDC 65C02

65C02 registers

15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00 (bit position) Main registers   A Accumulator Index registers   X X index   Y Y index 0 0 0 0 0 0 0 1 SP Stack Pointer Program counter PC Program Counter Status register   N V - B D I Z C Status Register

The Western Design Center (WDC) 65C02 microprocessor is an enhanced CMOS version of the popular NMOS-based 8-bit MOS Technology 6502 microprocessor—the CMOS redesign being made by Bill Mensch in 1978. Over various periods of time, the 65C02 has been second-sourced by NCR, GTE, Rockwell, Synertek and Sanyo. The 65C02 has been used in some home computers, as well as in embedded applications, including medical-grade implanted devices.

The 65C02 is a low cost, general-purpose 8-bit microprocessor (8-bit registers and data bus) with a 16-bit program counter and address bus. The variable length instruction set and manually optimized core size are intended to make the 65C02 well suited for low power system-on-chip (SoC) designs.

A Verilog hardware description model is available for designing the W65C02S core into an application-specific integrated circuit (ASIC) or a field-programmable gate array (FPGA). As is common in the semiconductor industry, WDC offers a development system, which includes a developer board, an in-circuit emulator (ICE) and a software development system.

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