The CXP825P40 is a highly integrated CMOS 8-bit single chip microcomputer which is mainly composed of an 8-bit CPU, PROM, RAM, and I/O ports. This microcomputer features many other high-performance circuits in a single chip CMOS design, including an A/D converter, serial interface, timer/counter, timebase timer, capture timer/counter, fluorescent display tube controller/driver, remote control receiver. Also, the CXP825P40 provides the power-on reset function as well as the sleep/stop function which assures reduced power consumption. Being a PROM-incorporated version of the CXP82540 which has on-chip mask ROM, the CXP825P40 permits program writing. Therefore, it is ideally suited for use in system development stage evaluation and job lot procuction.