Keyestudio ESP32 - 4. Test Code

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ESP32 Starter Kit

3. Wiring Diagram

4. Test Code

keyestudio ESP32 Inventor Learning Kit

Project 28 Intelligent Gate

http://www.keyestudio.com

#define servo_pin 25

int distance = 0; //Define a variable to receive the distance

int EchoPin = 14; //Connect Echo pin to IO14

int TrigPin = 13; //Connect Trig pin to IO13

//Ultrasonic ranging program

float checkdistance() { //Acquire distance

//preserve a short low level to ensure a clear high pulse:

digitalWrite(TrigPin, LOW);

delayMicroseconds(2);

//Trigger the sensor by a high pulse of 10um or longer

digitalWrite(TrigPin, HIGH);

delayMicroseconds(10);

digitalWrite(TrigPin, LOW);

//Read the signal from the sensor: a high level pulse

//Duration is detected from the point sending "ping" command to the time receiving␣

˓→echo signal (unit: um).

float distance = pulseIn(EchoPin, HIGH) / 58.00; //Convert into distance

delay(10);

return distance;

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