54 lines
1.4 KiB
Arduino
54 lines
1.4 KiB
Arduino
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/*********
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Rui Santos
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Complete project details at https://RandomNerdTutorials.com/esp32-hc-sr04-ultrasonic-arduino/
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Permission is hereby granted, free of charge, to any person obtaining a copy
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of this software and associated documentation files.
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The above copyright notice and this permission notice shall be included in all
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copies or substantial portions of the Software.
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*********/
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const int trigPin = 5;
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const int echoPin = 18;
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//define sound speed in cm/uS
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#define SOUND_SPEED 0.034
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#define CM_TO_INCH 0.393701
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long duration;
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float distanceCm;
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float distanceInch;
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void setup() {
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Serial.begin(115200); // Starts the serial communication
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pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
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pinMode(echoPin, INPUT); // Sets the echoPin as an Input
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}
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void loop() {
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// Clears the trigPin
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digitalWrite(trigPin, LOW);
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delayMicroseconds(2);
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// Sets the trigPin on HIGH state for 10 micro seconds
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digitalWrite(trigPin, HIGH);
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delayMicroseconds(10);
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digitalWrite(trigPin, LOW);
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// Reads the echoPin, returns the sound wave travel time in microseconds
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duration = pulseIn(echoPin, HIGH);
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// Calculate the distance
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distanceCm = duration * SOUND_SPEED/2;
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// Convert to inches
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distanceInch = distanceCm * CM_TO_INCH;
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// Prints the distance in the Serial Monitor
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Serial.print("Distance (cm): ");
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Serial.println(distanceCm);
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Serial.print("Distance (inch): ");
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Serial.println(distanceInch);
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delay(1000);
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}
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