IN80CL31N

 The IN80CL31N is a high-performance microcontroller fabricated with high-density CMOS technology. The instruction set is based on that the 80C51.The 80CL51 is general purpose microcontroller especially suited for battery powered  applications. The device has low power consumption and a wide range of supply voltage.

The IN80CL31N contains a 4k×8 ROM , a  128×8 RAM , 32 I/O lines, two 16-bit counter/timers, a five-source, two-priority level nested interrupt structure, a serial I/O port for  either multi-processor communications, I/O expansion or full duplex UART, and on-chip oscillator and clock circuits.

The IN80CL31N has two software selectable modes of power reduction - idle mode and power-down mode. The idle mode freezes the CPU while allowing the RAM, timers, serial port, and interrupt system to continue functioning. The power-down mode saves the RAM contents but freezes the oscillator, causing all other chip functions to be inoperative.