8Bit MCU Flash, 89C55, DIP40 - 

The AT89C55WD-24PU is a 8-bit low-power High-performance CMOS Microcontroller with 20kB of flash programmable read only memory and 256 bytes of RAM. The device is manufactured using Atmel's high-density non-volatile memory technology and is compatible with the industry standard 80C51 and 80C52 instruction set and pinout. The on-chip Flash allows the program memory to be user programmed by a conventional non-volatile memory programmer. By combining a versatile 8-bit CPU with flash on a monolithic chip, the Atmel AT89C55WD is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications. The AT89C55WD provides the following standard features 20kB of Flash, 256 bytes of RAM, 32 I/O lines, three 16-bit timer/counters, a six-vector, two-level interrupt architecture, a full-duplex serial port, on-chip oscillator and clock circuitry.