Electrical parameters: JSN-SR04T Operating voltage: DC 5V Quiescent current: 5mA Total current work: 30mA Acoustic emission frequency: 40khz Farthest distance: 4.5m Blind: 25cm Wiring: + 5V (positive power supply) Trig (control side) RX Echo (the receiver) TX GND (negative) Module size: 41mm * 28.5mm Resolution: about 0.5cm Angle: less than 50 degrees Working temperature: -10 ~ 70 ° Storage temperature: -20 ~ 80 ° Product Features: 1, small size, easy to use; 2, low voltage, low power consumption; 3, high accuracy; 4, strong anti-jamming; 5, integrated with wire enclosed waterproof probe, suitable for wet, harsh measurement occasions. Application: 1, Horizontal distance; 2, obstacle avoidance, automatic control; 3, the object approaches, there is a perceived 4, traffic control; 5, security, industrial control; 6, artificial intelligence, and research The basic working principle: (1) using IO port TRIG trigger location, to the high level signal of at least 10us; (2) module automatically sends 8 40KHz Fang Bo, automatic detecting whether a signal return; (3) a signal return, a high level is output through the IO port ECHO, the time duration of the high level is ultrasonic from launch to return. The test distance = (high level time * speed of sound (340M/S)) /2; This module uses the simple method, a control port with a 10US above high level, can wait for high level output at the receiving port. An output can drive the timer, when this port is low can read the timer value, this time for the location of the time, can be calculated distance. So constantly cycle test, that can achieve the measurement of the value of your mobile.