Lab 20/ HW 20

Lab 20 (SD Reader w/ Temp Data):

/Write to SD
#include <SD.h>
#include <Wire.h>
int temp_address = 72;
long previousMillis = 0;
int interval = 1000;
volatile long int timemax = 60000;
const int button1 = 2;
const int button2 = 3;
//Set by default for the SD Card Library
//MOSI = pin 11
//MISO = pin 12
//SCLK = pin 13
//We always need to set the CS Pin
const int CS_PIN = 10;
void setup()
{
  Serial.begin(9600);
  attachInterrupt(digitalPinToInterrupt(button1), increase, RISING);
  attachInterrupt(digitalPinToInterrupt(button2), decrease, RISING); 
  Wire.begin();
  Serial.println("Initializing Card");
  //CS pin is an output
  pinMode(CS_PIN, OUTPUT);
  if (!SD.begin(CS_PIN))
  {
    Serial.println("Card Failure");
    return;
  }
  Serial.println("Card Ready");
}
void increase()
{
  timemax = timemax + 1000;
  Serial.print("New Time Interval: ");
  Serial.println(timemax);
}
void decrease()
{
  timemax = timemax - 1000;
  Serial.print("New Time Interval: ");
  Serial.println(timemax);
}
void loop()
{
  if(millis() < timemax)
  {
  unsigned long timeStamp = millis();
  if(timeStamp - previousMillis >= interval)
  {
  previousMillis = timeStamp;
  Wire.beginTransmission(temp_address);
  Wire.write(0);
  Wire.endTransmission();
  Wire.requestFrom(temp_address, 1);
  int c = Wire.read();

  //Open a file and write to it.
  File dataFile = SD.open("temp.csv", FILE_WRITE);
  if (dataFile)
  {
    dataFile.print(timeStamp);
    dataFile.print(",");
    dataFile.print(c);
    dataFile.println(" C");
    dataFile.close(); //Data isn't actually written until we close the connection!
    //Print to serial monitor for debugging
    Serial.print(timeStamp);
    Serial.print(",");
    Serial.print(c);
    Serial.println(" C");
  }
  else
  {
    Serial.println("Couldn't open log file");
  }
  }
  }
  //Serial.println("Done Recording");
}