Keyestudio ESP32 Manual page 147

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
echo signal (unit: um).
float distance = pulseIn(EchoPin, HIGH)
delay(10);
return
distance;
}
void
setup() {
Serial.begin(9600);//Set the baud rate to 9600
pinMode(TrigPin, OUTPUT);//Set Trig pin to output
pinMode(EchoPin, INPUT);
}
void
loop() {
distance = checkdistance();
if(distance
< 10){
tone(beeppin, 262);//Play DO
delay(1000);
}
if(distance
< 20 &&
tone(beeppin, 294);//Play Re
delay(1000);
}
if(distance < 30 &&
tone(beeppin, 330);//Play Mi
delay(1000);
}
if(distance
< 40 &&
tone(beeppin, 349);//Play fa
delay(1000);
}
if(distance < 50 &&
tone(beeppin, 392);//Play So
delay(1000);
}
if(distance < 60 &&
tone(beeppin, 440);//Play La
delay(1000);
}
if(distance
< 70 &&
tone(beeppin, 494);//Play Si
delay(1000);
}
Serial.println(distance);
noTone(beeppin);//Stop
}
8.5. Arduino Project
//Set Echo pin to input
distance > 10){
distance > 20){
distance > 30){
distance > 40){
distance > 50){
distance > 60){
/ 58.00; //Convert into distance
ESP32 Starter Kit
(continued from previous page)
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