SN8P1917 is a high-performance 8-bit microcontroller with the 2K-word of the OTP ROM. The SN8P1917 provides the following features: 128 bytes of RAM, one 8-bit basic timer (T0) with RTC (Real Time Clock) function, a watchdog timer, two interrupt sources (T0, INT0), a 16-bit ADC, a PGIA, a charge pump/regulator, a integrated LCD driver for 4-common x 12 -segments LCD panel and a 8-level stack register. In addition, the SN8P1917 is a dual clock system, i.e. there are high-speed clock and low-speed clock. The high-speed clock is generated from the external 4MHz oscillator or on-chip 4MHz high-speed RC oscillator circuit.