The device is designed with the excellent IC structure including the program memory up to 4K-word OTP ROM, data memory of 256-bytes RAM, one 8-bit basic timer (T0), two 8-bit timer counters (TC0, TC1), a watchdog timer, eight interrupt sources (T0, TC0, TC1, SIO, ADC, INT0, INT1, INT2), a 7-bit DAC converter, an 8-channel 12-bit ADC converter, two channels PWM output (PWM0, PWM1), two channels buzzer output (BZ0, BZ1) and 8-level stack buffers. There are four oscillator configurations to select for generating system clock, including High/Low Speed crystal, ceramic resonator or cost-saving RC. This device also includes an internal RC oscillator for slow mode controlled by programming.