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