Description: Adopts IO port for at least 10us high level signal. It can send eight 40khz square wave automatically, and detect if there is any signal returned. If the signal returning, output one high level signal via IO port. The duration of the high level signal is the time from sending ultrasonic to returning. Measuring distance=duration of high level x sound velocity(340m/s)/2 Wide voltage operation: 3v-5.5v, sensing distance 5v: 2-450m; 3.3v: 2-400m Specification: : HC-SR04P ultrasonic module Working voltage : DC 3V-5.5V Static current: Less than 2mA Output signal: Electric frequency signal, high level 5V, low level 0V Sensor angle: No more than 15 degrees Detection distance: 2cm~450cm High precision: Up to 0.3cm Echo signal : output TTL PWL signal of connection: VCC; trig(T); echo(R); GND Package Includes: 1 Piece Ultrasonic Distance Measuring Module Note: The output can be started by the timer. When this port become low level, it can read the value of the timer. At this time, it is the time of this distance measurement.So it can calculate the distance, you can reach the value of your mobile measurement according to such continuous cycle test