Arduino code for MAX6675

.from: https://github.com/codebendercc/arduino-files/blob/master/extra-libraries/max6675/max6675.cpp

X================================X max6675.h X================================X

// this library is public domain. enjoy!
// www.ladyada.net/learn/sensors/thermocouple

#if ARDUINO >= 100
 #include "Arduino.h"
#else
 #include "WProgram.h"
#endif

class MAX6675 {
 public:
  MAX6675(int8_t SCLK, int8_t CS, int8_t MISO);

  double readCelsius(void);
  double readFahrenheit(void);
  // For compatibility with older versions:
  double readFarenheit(void) { return readFahrenheit(); }
 private:
  int8_t sclk, miso, cs;
  uint8_t spiread(void);
};

X================================X max6675.cpp X================================X

// this library is public domain. enjoy!
// www.ladyada.net/learn/sensors/thermocouple

#include <avr pgmspace.h="pgmspace.h">
#include <util delay.h="delay.h">
#include <stdlib .h=".h">
#include "max6675.h"

MAX6675::MAX6675(int8_t SCLK, int8_t CS, int8_t MISO) {
  sclk = SCLK;
  cs = CS;
  miso = MISO;

  //define pin modes
  pinMode(cs, OUTPUT);
  pinMode(sclk, OUTPUT);
  pinMode(miso, INPUT);

  digitalWrite(cs, HIGH);
}
double MAX6675::readCelsius(void) {

  uint16_t v;

  digitalWrite(cs, LOW);
  _delay_ms(1);

  v = spiread();
  v &lt;&lt;= 8;
  v |= spiread();

  digitalWrite(cs, HIGH);

  if (v &amp; 0x4) {
    // uh oh, no thermocouple attached!
    return NAN;
    //return -100;
  }

  v &gt;&gt;= 3;

  return v*0.25;
}

double MAX6675::readFahrenheit(void) {
  return readCelsius() * 9.0/5.0 + 32;
}

byte MAX6675::spiread(void) {
  int i;
  byte d = 0;

  for (i=7; i&gt;=0; i--)
  {
    digitalWrite(sclk, LOW);
    _delay_ms(1);
    if (digitalRead(miso)) {
      //set the bit to 0 no matter what
      d |= (1 &lt;&lt; i);
    }

    digitalWrite(sclk, HIGH);
    _delay_ms(1);
  }

  return d;
}

X================================X X================================X


</stdlib></util></avr>