| 摘要 |
PURPOSE: A method of testing the speed of a driving car employing variable reference clock and a device thereof are provided to test the speed at intervals using different periods and thereby minimize measurement errors. CONSTITUTION: In a method of testing the speed of a driving car, a step(120) verifies whether overflow has occurred. If overflow has not occurred(130), the result of the first step(110) is sent to the buffer and stays there for a while. In step(140), the driving speed is calculated using values detected at various intervals saved in the buffer and a reference clock for future testing is determined referring to the calculated speed. In step(150), the counter is enabled for future testing. In step(160), a cycle_time_flag is cleared as zero and the whole operation comes to an end. |
