Tears For Fears Songs From The Big Chair Remastered Youtube. This post shows a simple interfacing of an Arduino UNO board with HC-SR04 ultrasonic sensor in order to build a distance meter with a range up to 4 meters. The HC-SR04 ultrasonic sensor module can measure distances form 2 cm to 400 cm (4 m) with an accuracy of 3 mm. The HC-SR04 module includes ultrasonic transmitter, ultrasonic receiver and control circuit. The HC-SR04 ultrasonic sensor module has 4 pins as shown in the image below where: VCC: Positive power supply (+5V) Trig: Trigger input pin Echo: Echo output pin GND: Ground (0V) HC-SR04 ultrasonic sensor timing diagram: The timing diagram of the HC-SR04 ultrasonic sensor is shown below. Fl92 Drivers. First we have to supply the sensor trigger pin with a pulse of 10µs and the sensor will automatically send 8 cycles burst of ultrasound at 40 kHz and raise its echo pin. The Echo is a distance object that is pulse width and the range in proportion. We can calculate the range through the time interval between sending trigger signal and receiving echo signal.