1. General Description This EPROM-Based 8-bit micro-controller uses a fully static CMOS technology process to achieve higher speed and smaller size with the low power consump-tion and high noise immunity. On chip memory inclu-des 1K words of ROM, and 41 bytes of static RAM. 2. Features The followings are some of the features on the hardware and software : ? Fully COMS static design ? 8-bit data bus ? On chip EPROM size : 1 K words ? Internal RAM size : 41 bytes ? 36 single word instructions ? 14-bit instructions ? 2-level stacks ? Operating voltage : 2.5 V ~ 5.0 V ? Operating frequency : 4 MHz or 8 MHz ? The most fast execution time is 500 ns under 8 MHz in all single cycle instructions except the branch instruction ? Addressing modes include direct, indirect and relative addressing modes ? Power-on Reset ? Sleep Mode for power saving ? Oscillator mode: INTRC-Internal 4/8 MHz RC oscillator ? Power on start-up time : 20 ms ? 8-bit real time clock/counter(RTCC) with 8-bit programmable prescaler ? On-chip RC oscillator based Watchdog Timer(WDT) ? Wake-up from sleep on pin change 3. Applications The application areas of this P509(A) range from appliance motor control and high speed automotive to low power remote transmitters/receivers, small instruments, chargers, toy, automobile and PC pe-ripheral … etc.