Module Working Principle:
1. Adopt IO trigger through supplying at least 10us sequence of the high-level signal.
2. The module automatically sends eight 40khz square waves and automatically detect whether receive
the returning pulse signal.
3. If there are signals returning, by outputting high level and the time of high level continuing is
the time of that from the ultrasonic transmitting to receiving. Test distance =(high level time * sound velocity (340M/S) / 2.
This module is not suitable to connect with electric power if you need to connect this module with
electronic power, then let the GND terminal of this module to be connected first, otherwise, it will affect the normal work of the module
1 x HC-SR04 Ultrasonic Module Distance Measuring Transducer