On the basis of analyzing the working principle of ADC and touch screen for resistance, using ADC and GPIO module of the microprocessor LM3S3749 instead of dedicated controller ADS7846 touch screen. The hardware connection between LM3S3749 and LCD touch screen Interface circuit was designed, and a necessary program flowchart and function code was given. The method of obtaining coordinates of touch screen and the algorithms of LCD screen display synchronization were proposed to improve the efficiency of touch screen and LCD screen, and to satisfy the control precision.