How to read frequency with Arduino

Other Hardware Sensors
1

Hello All,

I choose to measure soil moisture with a Watermark sendor and an electric interface for Watermark (SMX)
The SMX give 3 options to read the result: Voltage, courent and frequency.
Look at the page 3, first schema. There is a small paragraph about freuency output.

I created my breadboard but I have not test it yet because I have no expertise to develop a code to read the frequency with a digital read.

I wonder if PulseIN or FreqCounter would help me read frequency on a digital pin connected to my sensor

It's look like FreqCounter whatch a Digital pin and return the frequency. That righ?

Someone can share an expemple or an experience?

Thank a lot

2

PulseIn will help you.

3

Here is an example of how to determine the frequency of an input. Put a frequency up to 28kHz into a digital pin, and an Arduino will output the frequency to the serial monitor:

// input pin can be any digital input
const byte inputPin = 2;

boolean inputState = false;
boolean lastInputState = false;
long count = 0L;

unsigned long previousCountMillis = millis();
const long countMillis = 500L;

void setInputState() {
  inputState = digitalRead(inputPin);
}

void setup() {
  pinMode(inputPin, INPUT);

  Serial.begin(115200);
}

void loop() {

  // runs every time thru the loop
  setInputState();
  
  // count every transision HIGH<->LOW
  if (inputState != lastInputState) {
    count++;  
    lastInputState = inputState;
  }

  // ------- every half second, count is equal to Hz.---------------
  if (millis() - previousCountMillis >= countMillis) {
    previousCountMillis += countMillis;
    
    // show Hz on Serial too if available
    Serial.print(count); 
    Serial.println(" Hz");

    // reset to zero for the next half second's sample
    count = 0L;
  }
}