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如何从Arduino Lilypad温度传感器获取环境温度

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我正在将LilyPad Temperature sensor连接到LilyPad Arduino 328 Main Board，目的是读取相当准确的环境温度读数 . 传感器正在接收电源并给出我能够通过串行读取的响应 .

我遇到的问题是从传感器读取给我非常不寻常的 - 虽然数字一致 . 我正在读模拟传感器输入并转换成这样的伏特......

loop(){
    float therm;   
    therm = analogRead(2); // Read from sensor through Analog 2
    therm *= (5.0/1024.0); // 5 volts / 1024 units of analog resolution
    delay(100);
}

这产生了大约1.1伏的一致读数，当真实环境温度为大约23度时，传感器文献表明该环境温度约为60摄氏度 . 传感器并不靠近任何其他电子设备，所以我无法预见到问题所在 .

我的传感器读取代码是不正确的？我的传感器可能有问题吗？

arduino microcontroller

3 回答

  • 0

    Lilypad不是3.3V arduino，这意味着它应该是 (3.3/1024.0) ，这将是0.726V，或22.6 C？

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  • 7

    试试这个 . 我有完全相同的问题 . 在这里阅读更多：http://www.ladyada.net/learn/sensors/tmp36.html

    //TMP36 Pin Variables
int sensorPin = 0; //the analog pin the TMP36's Vout (sense) pin is connected to
                        //the resolution is 10 mV / degree centigrade with a
                        //500 mV offset to allow for negative temperatures

#define BANDGAPREF 14   // special indicator that we want to measure the bandgap

/*
 * setup() - this function runs once when you turn your Arduino on
 * We initialize the serial connection with the computer
 */
void setup()
{
  Serial.begin(9600);  //Start the serial connection with the computer
                       //to view the result open the serial monitor 
  delay(500);
}

void loop()                     // run over and over again
{
  // get voltage reading from the secret internal 1.05V reference
  int refReading = analogRead(BANDGAPREF);  
  Serial.println(refReading);

  // now calculate our power supply voltage from the known 1.05 volt reading
  float supplyvoltage = (1.05 * 1024) / refReading;
  Serial.print(supplyvoltage); Serial.println("V power supply");

  //getting the voltage reading from the temperature sensor
  int reading = analogRead(sensorPin);  

  // converting that reading to voltage
  float voltage = reading * supplyvoltage / 1024; 

  // print out the voltage
  Serial.print(voltage); Serial.println(" volts");

  // now print out the temperature
  float temperatureC = (voltage - 0.5) * 100 ;   //converting from 10 mv per degree wit 500 mV offset
                                               //to degrees ((volatge - 500mV) times 100)
  Serial.print(temperatureC); Serial.println(" degress C");

  // now convert to Fahrenheight
  float temperatureF = (temperatureC * 9 / 5) + 32;
  Serial.print(temperatureF); Serial.println(" degress F");

  delay(1000);                                     //waiting a second
}
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  • 3

    根据这个documentation，analogRead返回一个整数 . 您是否尝试将其投射到浮动状态，如下所示：

    therm = (float)analogRead(2);

    电压表上的传感器电压读数是多少？更改传感器温度时读数是否会改变？ （握住它应该足以改变读数 . ）

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