Ultrasonic Sensor receiving Side

Question

I'm doing my project regarding 40khz ultrasonic sensor which will be used to get accurate distance measurements. I have a separate transmitter and receiver. I want to get the time between the moment my transmitter transmitted the waves and the time my receiver received it. However, I couldn't actually make it work. Does any of you give me a code that would help me transmit and receive the 40khz waves and get the time in between so I could use it to compute for the distance?Thank you in advance. I would greatly appreciate it!

Answer 1

This is the most basic ultrasound pulse and receive code. I wrote it to work with the HC-SR04 modules; so hopefully it will work fro you too as those also sound at 40khz.

The main functionality comes from the pulseIn() funciton.

#define TRIGPIN 9
#define ECHOPIN 10

void setup() {
  Serial.begin(9600);
  pinMode(TRIGPIN, OUTPUT);
  pinMode(ECHOPIN, INPUT);
}

void loop() {
  digitalWrite(TRIGPIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIGPIN, LOW);

  uint16_t duration = pulseIn(ECHOPIN, HIGH, 4000);
  int distance = (duration*.0343)/2;
  Serial.println(distance);
}

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Note that you will need to adjust the 4000 (μs) to whatever timeout in you want (or emit entirely if you don't want it).

Answer 2

I don't have 'a code', but what you can do is using a timer set to 40 kHz and send the pulses you need. .

If nothing else needs to be done (nor in the future) you can use a delay function.

Also check the pulseIn function from Arduino, you can use this convenience function for the checking the result.