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The Ricoh 5A22 is a microprocessor produced by Ricoh for the Super Nintendo Entertainment System (SNES) video game console. The 5A22 is based on the 8/16-bit CMD/GTE 65c816, itself a version of the WDC 65C816 (used in the Apple IIGS personal computer). It has an 8-bit data bus, a 16-bit accumulator, a 24-bit address bus, and is based on the MOS Technology 6502 family of processors.


Major featuresEdit

Ricoh 5A22

In addition to the 65C816 CPU core, the 5A22 contains support hardware, including:


The CPU as a whole employs a variable-speed system bus, with bus access times determined by the memory location accessed. The bus runs at 3.58 MHz for non-access cycles and when accessing Bus B and most internal registers, and either 2.68 or 3.58 MHz when accessing Bus A. It runs at 1.79 MHz only when accessing the controller port serial-access registers.[1] It works at approximately 1.5 MIPS, and has a theoretical peak performance of 1.79 million 16-bit operations per second.

See alsoEdit


  1. ^ anomie (December 21, 2008). "Anomie's SNES Memory Mapping Doc" (text). Retrieved June 19, 2019.