代码收藏家技术教程 2024-12-06

ph监测传感器连接arduino，stm32,51单片机使用

一.传感器介绍

溶液的酸碱度(PH值)是溶液的一个重要特性。工业级PH变送器价格昂贵;市面上的PH测试笔是成熟产品，无法进行二次设计开发; PH复合电极输出mV级的电压信号，单片机无法直接进行识别处理，基于这些现状我们设计了这款PH传感器模块。该模块价格低廉、使用方便、测量精度高、可直接输出0~5V或0~3V模拟电压信号。

二.使用用

2.1

arduino接线使用及相关代码。

#define SensorPin A1            //pH meter Analog output to Arduino Analog Input 1
#define Offset 17.677           //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 = -5.8887*voltage+Offset;
      if(pHValue<=0.0){pHValue=0.0;}
      if(pHValue>14.0){pHValue=14.0;}
      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;
}

2.2

51单片机

STC89+PCF8591-1602显示