Cara Menggunakan Sensor PH Meter (SKU: SEN0161) Dengan Arduino

Contoh Program:

#define SensorPin A0 //pH meter Analog output to Arduino Analog Input 0

#define Offset 0.00 //deviation compensate

#define LED 13

#define samplingInterval 20

#define printInterval 800

#define ArrayLenth 40 //times of collection

int pHArray[ArrayLenth]; //Store the average value of the sensor feedback

int pHArrayIndex = 0;

void setup(void)

{

  pinMode(LED, OUTPUT);

  Serial.begin(9600);

  Serial.println("pH meter experiment!"); //Test the serial monitor

}

void loop(void)

{

  static unsigned long samplingTime = millis();

  static unsigned long printTime = millis();

  static float pHValue, voltage;

  if (millis()-samplingTime > samplingInterval)

  {

    pHArray[pHArrayIndex++] = analogRead(SensorPin);

    if (pHArrayIndex == ArrayLenth)pHArrayIndex = 0;

    voltage = avergearray(pHArray, ArrayLenth) * 5.0 / 1024;

    pHValue = 3.5 * voltage + Offset;

    samplingTime = millis();

  }

  if (millis() - printTime > printInterval) //Every 800 milliseconds, print a numerical, convert the state of the LED indicator

  {

    Serial.print("Voltage:");

    Serial.print(voltage, 2);

    Serial.print(" pH value: ");

    Serial.println(pHValue, 2);

    digitalWrite(LED, digitalRead(LED) ^ 1);

    printTime = millis();

  }

}

double avergearray(int* arr, int number) {

  int i;

  int max, min;

  double avg;

  long amount = 0;

  if (number <= 0) {

    Serial.println("Error number for the array to avraging!/n");

    return 0;

  }

  if (number < 5) { //less than 5, calculated directly statistics

    for (i = 0; i < number; i++) {

      amount += arr[i];

    }

    avg = amount / number;

    return avg;

  } else {

    if (arr[0] < arr[1]) {

      min = arr[0]; max = arr[1];

    }

    else {

      min = arr[1]; max = arr[0];

    }

    for (i = 2; i < number; i++) {

      if (arr[i] < min) {

        amount += min; //arr<min

        min = arr[i];

      } else {

        if (arr[i] > max) {

          amount += max; //arr>max

          max = arr[i];

        } else {

          amount += arr[i]; //min<=arr<=max

        }

      }//if

    }//for

    

    avg = (double)amount / (number-2);

  }//if

  return avg;

}