The MSM65516 is a high-performance 8-bit microcontroller that employs OKI original nX-8/50 CPU core. With a minimum instruction execution time of 400 ns (10MHz clock), the MSM65516 is capable of high-speed processing, and includes 32K bytes of program memory, 640 bytes of data memory, timers and serial ports. Also available are the MSM65P516, which replaces the onchip program memory with one-time PROM, and the MSM65X516, which uses external program memory.