The W65816 (also: 65C816), a 16-bit microprocessor developed by the Western Design Center (WDC), is an expanded and compatible successor to the venerable MOS Technology 6502. The 65816 has two 16-bit index registers, a stack pointer, a 16-bit direct page register , and a 24-bit address bus.

Notable uses of the W65816

• Apple IIGS (2.8 MHz)
• Super Famicom/Super Nintendo video game consoles (3.58 MHz)
• SuperCPU accelerators for the Commodore 64 and 128 (20 MHz)
• 65C816ADP "Hyper-Speed" accelerators for the Atari XL /Atari XE (1.79/14 MHz)
• C-One (Commodore One) FPGA-based reconfigurable computer (20 MHz)
• The Mensch Computer (using the W65C265 microcontroller)

References

• Eyes, David; Lichty, Ron (1986). Programming the 65816 including the 6502, 65C02, and 65802. New York: Brady/Prentice Hall. ISBN 0-89303-789-3.

External links

• W65C816S information from WDC – With link to datasheet in PDF
• A 6502 Programmer's Introduction to the 65816 – By Brett Tabke, with instruction set summary from Creative Micro Designs.