Temperature and Light Sensor Data Logger

In this tutorial I make a temperature and light sensor data logger with an Arduino so that I can test different locations for plants or places to sleep outside in the summer that don't get to much sun

Step 1: Things You Will Need

1 Arduino board

1 Breadboard

1 Photoresistor

1 Temperature Sensor

1 SD Card

1 SD Card Reader

1 9v Battery

Jumper Wires

Step 2: Assembly

Hook up the SD card reader:

MOSI - pin 11

MISO - pin 12

CLK - pin 13

CS - pin 4

Gnd - Gnd

5v - 5v

3.3v - NOTHING

Other Gnd - Gnd

Photoresistor:

One end to 5v and the other end to pin2

after the cable to pin 2 there should be a resistor to gnd

Temperature Sensor:

Gnd - Gnd

Vin - 5v (it an also be to 3.3v but you will need to change the code)

Central Pin - Pin3

SD card:

Plug it in (:

Step 3: Code

/*
 ** MOSI - pin 11
 ** MISO - pin 12
 ** CLK - pin 13
 ** CS - pin 4
 */
#include 
#include 
#define PhotoresistorPin 2
#define TempPin 3
const int chipSelect = 4;
String FileName = "DataLog.txt";
long int LastLog;
void setup()
{
  Serial.begin(9600);
  pinMode(TempPin, INPUT);
  pinMode(PhotoresistorPin, INPUT);
  pinMode(13, OUTPUT);
  Serial.print("Initializing SD card...");
  // make sure that the default chip select pin is set to
  // output, even if you don't use it:
  pinMode(10, OUTPUT);
  // see if the card is present and can be initialized:
  if (!SD.begin(chipSelect)) {
    Serial.println("Card failed, or not present");
    //turns on the onboard led to signal that something is wrong
    digitalWrite(13,HIGH);
    
    // don't do anything more:
    return;
  }
  Serial.print("Card initialized.");
}
void loop()
{
  
  //delays 10 minutes 
  while (LastLog + 600000 > millis()) {
    delay(1000);
  }
  
  
  int PhotoResistance = GetPhotoresistence();
  float Temparature = GetTemperature();
  LogData(PhotoResistance, Temparature);
}
void LogData(int Resistance, int Temparature) {
  //the file you edit
  File dataFile;
  dataFile = SD.open(FileName, FILE_WRITE);
  dataFile.print("Minutes Running:");
  dataFile.print(millis() / 60000);
  dataFile.print("   Photoresistor: ");
  dataFile.print(Resistance);
  dataFile.print("   Temparature: ");
  dataFile.print(Temparature);
  dataFile.println("C");
  dataFile.close();
  LastLog = millis();
}
float GetTemperature() {
  float Temperature = analogRead(TempPin);
  Temperature = Temperature * 0.48828125;
  delay(1000);
  return Temperature;
}
int GetPhotoresistence() {
  int Photoresistence = analogRead(PhotoresistorPin);
  return Photoresistence;
}

Step 4: Finished!!

Now just plug in the battery and it will start logging data!