The AT89LS53 is a low-power, wide-voltage range, high-performance CMOS 8-bit microcomputer with 12K bytes of downloadable Flash programmable and erasable read-only memory. The device is manufactured using Atmel's high-density nonvolatile memory technology and is compatible with the industry standard 80C51 instruction set and pinout. The on-chip downloadable Flash allows the program memory to be reprogrammed in-system through an SPI serial interface or by a conventional nonvolatile memory programmer. By combining a versatile 8-bit CPU with downloadable Flash on a monolithic chip, the Atmel AT89LS53 is a powerful microcomputer which provides a highly flexible and cost-effective solution to many embedded control applications.