Adafruit_TMP006.cpp

/*************************************************** 
  This is a library for the TMP006 Temp Sensor

  Designed specifically to work with the Adafruit TMP006 Breakout 
  ----> https://www.adafruit.com/products/1296

  These displays use I2C to communicate, 2 pins are required to  
  interface
  Adafruit invests time and resources providing this open source code, 
  please support Adafruit and open-source hardware by purchasing 
  products from Adafruit!

  Written by Limor Fried/Ladyada for Adafruit Industries.  
  BSD license, all text above must be included in any redistribution
 ****************************************************/

#include "Adafruit_TMP006.h"

//#define TESTDIE 0x0C78
//#define TESTVOLT 0xFEED

Adafruit_TMP006::Adafruit_TMP006(uint8_t i2caddr) {
  _addr = i2caddr;
}


bool Adafruit_TMP006::begin(uint16_t samplerate) {

  write16(TMP006_CONFIG, TMP006_CFG_MODEON | TMP006_CFG_DRDYEN | samplerate);

  uint16_t mid, did;
  mid = read16(TMP006_MANID);
  did = read16(TMP006_DEVID);
#ifdef TMP006_DEBUG
  Serial.print("mid = 0x"); Serial.println(mid, HEX);
  Serial.print("did = 0x"); Serial.println(did, HEX);
#endif
  if (mid != 0x5449) return false;
  if (did != 0x67) return false;
  return true;
}

bool Adafruit_TMP006::sleep() {
  // Read the control register and update it so bits 12-14 are zero to enter sleep mode.
  uint16_t control = read16(TMP006_CONFIG);
  control &= ~(TMP006_CFG_MODEON);
  return write16(TMP006_CONFIG, control);
}

bool Adafruit_TMP006::wake() {
  // Read the control register and update it so bits 12-14 are one to enter full operation.
  uint16_t control = read16(TMP006_CONFIG);
  control |= TMP006_CFG_MODEON;
  return write16(TMP006_CONFIG, control);
}

bool Adafruit_TMP006::drdy() {
  // Read the control register and read it so bit 7 can be returned
  uint16_t control = read16(TMP006_CONFIG);
  control &= TMP006_CFG_DRDY; 
  if (control>>7 == 1) {
	  return true;
  }
  return false;
}

//////////////////////////////////////////////////////

double Adafruit_TMP006::readDieTempC(void) {
   double Tdie = readRawDieTemperature();
   Tdie *= 0.03125; // convert to celsius
#ifdef TMP006_DEBUG
   Serial.print("Tdie = "); Serial.print(Tdie); Serial.println(" C");
#endif
   return Tdie;
}

double Adafruit_TMP006::readObjTempC(void) {
   double Tdie = readRawDieTemperature();
   double Vobj = readRawVoltage();
   Vobj *= 156.25;  // 156.25 nV per LSB
   Vobj /= 1000; // nV -> uV
   Vobj /= 1000; // uV -> mV
   Vobj /= 1000; // mV -> V
   Tdie *= 0.03125; // convert to celsius
   Tdie += 273.15; // convert to kelvin

#ifdef TMP006_DEBUG
   Serial.print("Vobj = "); Serial.print(Vobj * 1000000); Serial.println("uV");
   Serial.print("Tdie = "); Serial.print(Tdie); Serial.println(" C");
#endif
   
   double tdie_tref = Tdie - TMP006_TREF;
   double S = (1 + TMP006_A1*tdie_tref + 
                     TMP006_A2*tdie_tref*tdie_tref);
   S *= TMP006_S0;
   S /= 10000000;
   S /= 10000000;
   
   double Vos = TMP006_B0 + TMP006_B1*tdie_tref + 
                TMP006_B2*tdie_tref*tdie_tref;
   
   double fVobj = (Vobj - Vos) + TMP006_C2*(Vobj-Vos)*(Vobj-Vos);
   
   double Tobj = sqrt(sqrt(Tdie * Tdie * Tdie * Tdie + fVobj/S));
   
   Tobj -= 273.15; // Kelvin -> *C
   return Tobj;
}



int16_t Adafruit_TMP006::readRawDieTemperature(void) {
  int16_t raw = read16(TMP006_TAMB);

#if TMP006_DEBUG == 1

#ifdef TESTDIE
  raw = TESTDIE;
#endif

  Serial.print("Raw Tambient: 0x"); Serial.print (raw, HEX);
  

  float v = raw/4;
  v *= 0.03125;
  Serial.print(" ("); Serial.print(v); Serial.println(" *C)");
#endif
  raw >>= 2;
  return raw;
}

int16_t Adafruit_TMP006::readRawVoltage(void) {
  int16_t raw;

  raw = read16(TMP006_VOBJ);

#if TMP006_DEBUG == 1

#ifdef TESTVOLT
  raw = TESTVOLT;
#endif

  Serial.print("Raw voltage: 0x"); Serial.print (raw, HEX);
  float v = raw;
  v *= 156.25;
  v /= 1000;
  Serial.print(" ("); Serial.print(v); Serial.println(" uV)");
#endif
  return raw; 
}


/*********************************************************************/

uint16_t Adafruit_TMP006::read16(uint8_t a) {
  uint16_t ret;

  Wire.beginTransmission(_addr); // start transmission to device 
#if (ARDUINO >= 100)
  Wire.write(a); // sends register address to read from
#else
  Wire.send(a); // sends register address to read from
#endif
  Wire.endTransmission(); // end transmission
  
  //Wire.beginTransmission(_addr); // start transmission to device 
  Wire.requestFrom(_addr, (uint8_t)2);// send data n-bytes read
#if (ARDUINO >= 100)
  ret = Wire.read(); // receive DATA
  ret <<= 8;
  ret |= Wire.read(); // receive DATA
#else
  ret = Wire.receive(); // receive DATA
  ret <<= 8;
  ret |= Wire.receive(); // receive DATA
#endif
  //Wire.endTransmission(); // end transmission

  return ret;
}

bool Adafruit_TMP006::write16(uint8_t a, uint16_t d) {
  Wire.beginTransmission(_addr); // start transmission to device 
#if (ARDUINO >= 100)
  Wire.write(a); // sends register address to read from
  Wire.write(d>>8);  // write data
  Wire.write(d);  // write data
#else
  Wire.send(a); // sends register address to read from
  Wire.send(d>>8);  // write data
  Wire.send(d);  // write data
#endif
  byte retVal = Wire.endTransmission(); // end transmission
  if (retVal == 0) {
	  return true;
  }
  return false;
}