Abstract:

In order to solve the problem of the length measurement in industrial settings ,we designed a system measuring the stick length based on freescale microcontroller. This system used a freescale microcontroller as the key controller. There is a track driven by a DC (Direct Current) motor which is turning with a constant speed. We placed three groups infrared transmitting and receiving devices whose distance was equal on both sides of the track. Place the stick on the track and the internal timer began to  countime when the stick crossed the infrared device. Then we can get the moving time of the stick and obtaining the length of the stick. Finally, we used a 1602 monitor to display the length of the stick. Through the experiment ,the measurement error of this system was less than 0.05%.

Key words: freescale microcontroller, direct current motor, infrared device, timer