Counter program

Question

I'm an absolute beginner, and lately I had some problem with this program I was trying to do. Basically I wanted with the Arduino to count 3 pulses from an oscillator and store the time of these 3 pulses, but as I said I am a beginner so I have no Idea on how to do it, I would appreciate your help.

Answer 1

While this is likely to need tweaks for your needs, it should get you looking at the right things - millis, interrupts, etc. Official references at: https://www.arduino.cc/reference/en/language/functions/external-interrupts/attachinterrupt/ https://www.arduino.cc/reference/en/language/functions/time/millis/

#define pulsesToStore 3
#define interruptPin 2
volatile unsigned char index;
unsigned long storedTimes[pulsesToStore];

void restartStorage() {
 index = 0;
 attachInterrupt(digitalPinToInterrupt(interruptPin), storeTime, RISING);
}

void storeTime() {
 storedTimes[index] = millis();
 index = index + 1;
 if(index >= pulsesToStore) { //stop storage
  detachInterrupt(digitalPinToInterrupt(interruptPin));
 }
}

void setup() {
 pinMode(interruptPin, INPUT_PULLUP);
 restartStorage();
}

void loop() {
  // does nothing for now.  this is where you would do something with the stored pulses, print to serial, etc.
}

Answer 2

Simple code

int pin = 7;
unsigned long duration;

void setup() {
  Serial.begin(9600);
  pinMode(pin, INPUT);
}

void loop() {
long duration = pulseIn(pin, HIGH);
 Serial.println(duration);
//delay(100);
}

Assuming that you are mentioning a squrewave this code mesures the time that squrewave pulse stays in HIGH and prints out in computer serial monitor.

You should send the signal to digital pin 7 (or put any pin you won't modify code int pin = 7;) 5 V HIGH and 0 V LOW.

The time unit measuring in here is in microseconds. If you won't to measure low then pulseIn(pin, LOW);

I took the example from Arduino official site you can refer more here

https://www.arduino.cc/reference/en/language/functions/advanced-io/pulsein/

Remember this is the basic example there are other good methods than this...

Analog wave is bit too complex.