Low-power, high-performance CMOS 8-bit microcontroller with 20KB of flash programmable ROM and 256 bytes of RAM. The device is manufactured using Atmel high-density nonvolatile memory technology and is compatible with the industry standard 80C51 and 80C52 instruction set and pinout. On-chip flash allows the program memory to be user programmed by a conventional nonvolatile memory programmer. This versatile 8-bit CPU with flash is a highly flexible and cost-effective solution for many embedded control applications.