AT89C52 MCU is used as the system control module in the design of the Gasoline models to identify. Capacitance sensor will be inserted in gasoline, when the beginning of testing, the system through the single-chip timing, counters with the work, calculated at different dielectric constant of different gasoline in order to estimate the petrol models. As the dielectric constant can not be directly measured, so the dielectric constant will be converted into gasoline capacitance, changes in capacitance into a frequency shift to measure. Capacitance value will eventually be fitted with an octane number, LCD liquid crystal display through 1602 show that the petrol was measured models. This system can detect 93, 95, 97 and 100 petrol.
Key words：Gasoline identify MCU Permittivity
