Added begin and available functions, reworked examples for polling

Also added notes on packets being dropped, and tweaked the temperature reading syntax, added a soft resetToDefaults() function, currently working on -fpermissive enum typecasting stuff. This code probably doesn't work, just commiting so it's not lost.

Co-Authored-By: Fischer Moseley <fischermoseley@users.noreply.github.com>

Author: FischerMoseley

examples/Example1_BasicReadings/Example1_BasicReadings.ino

@@ -20,6 +20,7 @@ void setup(){
     Serial.begin(115200);
     Wire.begin();
     Wire.setClock(100000);
+    tempSensor.begin();
 
     //check if the sensor is connected
     if(tempSensor.isConnected()){
@@ -40,14 +41,16 @@ void setup(){
     }
 }
 
-void loop(){ //print the thermocouple, ambient and delta temperatures every 200ms
-    Serial.print("Thermocouple: ");
-    Serial.print(tempSensor.thermocoupleTemp());
-    Serial.print(" °C   Ambient: ");
-    Serial.print(tempSensor.ambientTemp());
-    Serial.print(" °C   Temperature Delta: ");
-    Serial.print(tempSensor.tempDelta());
-    Serial.print(" °C");
-    Serial.println();
-    delay(200);
+void loop(){ //print the thermocouple, ambient and delta temperatures every 200ms if available
+    if(tempSensor.available()){
+        Serial.print("Thermocouple: ");
+        Serial.print(tempSensor.getThermocoupleTemp());
+        Serial.print(" °C   Ambient: ");
+        Serial.print(tempSensor.getAmbientTemp());
+        Serial.print(" °C   Temperature Delta: ");
+        Serial.print(tempSensor.getTempDelta());
+        Serial.print(" °C");
+        Serial.println();
+        //delay(200);
+    }
 }

examples/Example2_SetThermocoupleType/Example2_SetThermocoupleType.ino

@@ -25,6 +25,7 @@ void setup(){
     Serial.begin(115200);
     Wire.begin();
     Wire.setClock(100000);
+    tempSensor.begin();
 
     //check that the sensor is connected
     if(tempSensor.isConnected()){
@@ -59,13 +60,15 @@ void setup(){
 }
 
 void loop(){ //print the thermocouple, ambient and delta temperatures every 200ms
-    Serial.print("Thermocouple: ");
-    Serial.print(tempSensor.thermocoupleTemp());
-    Serial.print(" °C   Ambient: ");
-    Serial.print(tempSensor.ambientTemp());
-    Serial.print(" °C   Temperature Delta: ");
-    Serial.print(tempSensor.tempDelta());
-    Serial.print(" °C");
-    Serial.println();
-    delay(200);
+    if(tempSensor.available()){
+        Serial.print("Thermocouple: ");
+        Serial.print(tempSensor.getThermocoupleTemp());
+        Serial.print(" °C   Ambient: ");
+        Serial.print(tempSensor.getAmbientTemp());
+        Serial.print(" °C   Temperature Delta: ");
+        Serial.print(tempSensor.getTempDelta());
+        Serial.print(" °C");
+        Serial.println();
+        delay(200);        
+    }
 }

examples/Example3_SetFilterCoefficient/Example3_SetFilterCoefficient.ino

@@ -11,6 +11,13 @@
   where 0 disables the filter, 1 corresponds to minimum filtering, and 7 enables maximum filtering. The "strength"
   of the filter just refers to how long it takes for the filter to respond to a step function input. 
 
+  Quick Note! For some reason the getFilterCoefficient() function is a little wierd about returning the proper
+  data. This is a known issue and while we've done our best to fix it, every once in a while it might return a 0,
+  or the wrong value entirely. We think this is an issue with the MCP9600, and there's not much we can do about it.
+  If you'd like to learn more or contact us, check out this issue on GitHub!
+
+  https://github.com/sparkfun/SparkFun_MCP9600_Arduino_Library/issues/1
+
   Hardware Connections:
   Attach the Qwiic Shield to your Arduino/Photon/ESP32 or other
   Plug the sensor onto the shield
@@ -66,15 +73,15 @@ void setup(){
 }
 
 void loop(){ //print the thermocouple, ambient and delta temperatures every 200ms
-    Serial.print("Thermocouple: ");
-    Serial.print(tempSensor.thermocoupleTemp());
-    Serial.print(" °C   Ambient: ");
-    Serial.print(tempSensor.ambientTemp());
-    Serial.print(" °C   Temperature Delta: ");
-    Serial.print(tempSensor.tempDelta());
-    Serial.print(" °C");
-    Serial.print("   Current coefficient: ");
-    Serial.print(tempSensor.getFilterCoefficient(), BIN);
-    Serial.println();
-    delay(200);
+    if(tempSensor.available()){
+        Serial.print("Thermocouple: ");
+        Serial.print(tempSensor.getThermocoupleTemp());
+        Serial.print(" °C   Ambient: ");
+        Serial.print(tempSensor.getAmbientTemp());
+        Serial.print(" °C   Temperature Delta: ");
+        Serial.print(tempSensor.getTempDelta());
+        Serial.print(" °C");
+        Serial.println();
+        delay(200);        
+    }
 }

examples/Example4_SetResolution/Example4_SetResolution.ino

@@ -74,13 +74,15 @@ void setup(){
 }
 
 void loop(){ //print the thermocouple, ambient and delta temperatures every 200ms
-  Serial.print("Thermocouple: ");
-  Serial.print(tempSensor.thermocoupleTemp());
-  Serial.print(" °C   Ambient: ");
-  Serial.print(tempSensor.ambientTemp());
-  Serial.print(" °C   Temperature Delta: ");
-  Serial.print(tempSensor.tempDelta());
-  Serial.print(" °C");
-  Serial.println();
-  delay(200);
+    if(tempSensor.available()){
+        Serial.print("Thermocouple: ");
+        Serial.print(tempSensor.getThermocoupleTemp());
+        Serial.print(" °C   Ambient: ");
+        Serial.print(tempSensor.getAmbientTemp());
+        Serial.print(" °C   Temperature Delta: ");
+        Serial.print(tempSensor.getTempDelta());
+        Serial.print(" °C");
+        Serial.println();
+        delay(200);        
+    }
 }

examples/Example5_BurstMode/Example5_BurstMode.ino

@@ -55,11 +55,11 @@ void loop(){
 
     //print the thermocouple, ambient and delta temperatures
     Serial.print("Thermocouple: ");
-    Serial.print(tempSensor.thermocoupleTemp());
+    Serial.print(tempSensor.getThermocoupleTemp());
     Serial.print(" °C   Ambient: ");
-    Serial.print(tempSensor.ambientTemp());
+    Serial.print(tempSensor.getAmbientTemp());
     Serial.print(" °C   Temperature Delta: ");
-    Serial.print(tempSensor.tempDelta());
+    Serial.print(tempSensor.getTempDelta());
     Serial.print(" °C");
     Serial.println();
 

examples/Example6_ConfigureTemperatureAlert/Example6_ConfigureTemperatureAlert.ino

@@ -90,11 +90,11 @@ uint16_t updateTime = 200;
 void loop(){
   if((clock + updateTime) < millis()){
     Serial.print("Thermocouple: ");
-    Serial.print(tempSensor.thermocoupleTemp());
+    Serial.print(tempSensor.getThermocoupleTemp());
     Serial.print(" °C   Ambient: ");
-    Serial.print(tempSensor.ambientTemp());
+    Serial.print(tempSensor.getAmbientTemp());
     Serial.print(" °C   Temperature Delta: ");
-    Serial.print(tempSensor.tempDelta());
+    Serial.print(tempSensor.getTempDelta());
     Serial.print(" °C");
 
     if(tempSensor.isTempGreaterThanLimit(risingAlert)){

src/SparkFun_MCP9600.cpp

@@ -26,14 +26,22 @@ Distributed as-is; no warranty is given.
 #include "WProgram.h"
 #endif
 
-//Class constructor
-MCP9600::MCP9600(uint8_t address, TwoWire &wirePort){
+/*-------------------------------- Device Status ------------------------*/
+
+bool MCP9600::begin(uint8_t address, TwoWire &wirePort){
   _deviceAddress = address; //grab the address that the sensor is on
   _i2cPort = &wirePort; //grab the port that the user wants to use
+  
+  //return true if the device is connected and the device ID is what we expect
+  bool success = isConnected();
+  success &= checkDeviceID();
+  return success;
 }
 
-
-/*-------------------------------- Device Status ------------------------*/
+bool MCP9600::available(){
+  uint8_t status = readSingleRegister(SENSOR_STATUS);
+  return bitRead(status, 6);
+}
 
 bool MCP9600::isConnected(){
   _i2cPort->beginTransmission(_deviceAddress);
@@ -48,25 +56,51 @@ bool MCP9600::checkDeviceID(){
   return (highByte(deviceID()) == DEV_ID_UPPER);
 }
 
+bool MCP9600::resetToDefaults(){
+  bool success = writeSingleRegister(SENSOR_STATUS, 0x00);
+  success |= writeSingleRegister(THERMO_SENSOR_CONFIG, 0x00);
+  success |= writeSingleRegister(DEVICE_CONFIG, 0x00);
+  success |= writeSingleRegister(ALERT1_CONFIG, 0x00);
+  success |= writeSingleRegister(ALERT2_CONFIG, 0x00);
+  success |= writeSingleRegister(ALERT3_CONFIG, 0x00);
+  success |= writeSingleRegister(ALERT4_CONFIG, 0x00);
+  success |= writeSingleRegister(ALERT1_HYSTERESIS, 0x00);
+  success |= writeSingleRegister(ALERT2_HYSTERESIS, 0x00);
+  success |= writeSingleRegister(ALERT3_HYSTERESIS, 0x00);
+  success |= writeSingleRegister(ALERT4_HYSTERESIS, 0x00);
+  success |= writeDoubleRegister(ALERT1_LIMIT, 0x0000);
+  success |= writeDoubleRegister(ALERT2_LIMIT, 0x0000);
+  success |= writeDoubleRegister(ALERT3_LIMIT, 0x0000);
+  success |= writeDoubleRegister(ALERT4_LIMIT, 0x0000);
+  return success;
+}
 
 /*----------------------------- Sensor Measurements ---------------------*/
 
 float MCP9600::getThermocoupleTemp(bool units){
+  //read register and convert to celcius
   int16_t raw = readDoubleRegister(HOT_JUNC_TEMP);
   float celcius = ((float)raw * DEV_RESOLUTION);
-  units ? return celcius; : return (((float)celcius * 1.8f) + 32);
+
+  //clear data ready bit
+  uint8_t status = readSingleRegister(SENSOR_STATUS);
+  bitWrite(status, 6, 0);
+  writeSingleRegister(SENSOR_STATUS, status);
+
+  //return in celcius or freedom units
+  return units ? celcius : (((float)celcius * 1.8f) + 32);
 }
 
 float MCP9600::getAmbientTemp(bool units){
   int16_t raw = readDoubleRegister(COLD_JUNC_TEMP);
   float celcius = ((float)raw * DEV_RESOLUTION);
-  units ? return celcius; : return (((float)celcius * 1.8f) + 32);
+  return units ? celcius : (((float)celcius * 1.8f) + 32);
 }
 
 float MCP9600::getTempDelta(bool units){
   int16_t raw = readDoubleRegister(DELTA_JUNC_TEMP);
   float celcius = ((float)raw * DEV_RESOLUTION);
-  units ? return celcius; : return (((float)celcius * 1.8f) + 32);
+  return units ? celcius : (((float)celcius * 1.8f) + 32);
 }
 
 signed long MCP9600::getRawADC(){
@@ -103,7 +137,7 @@ bool MCP9600::setAmbientResolution(Ambient_Resolution res){
 
 Ambient_Resolution MCP9600::getAmbientResolution(){
   uint8_t config = readSingleRegister(DEVICE_CONFIG); //grab current device configuration 
-  return bitRead(config, 7); //return 7th bit from config register
+  return static_cast<Ambient_Resolution>(bitRead(config, 7)); //return 7th bit from config register
 }
 
 bool MCP9600::setThermocoupleResolution(Thermocouple_Resolution res){
@@ -125,7 +159,7 @@ Thermocouple_Resolution MCP9600::getThermocoupleResolution(){
   bool lowResolutionBit = bitRead(config, 5);
   bitWrite(res, 1, highResolutionBit); //set 1st bit of the enum to the 6th bit of the config register
   bitWrite(res, 0, lowResolutionBit); //set 0th bit of the enum to the 5th bit of the config register
-  return res;
+  return static_cast<Thermocouple_Resolution>(res);
 }
 
 uint8_t MCP9600::setThermocoupleType(Thermocouple_Type type){
@@ -142,7 +176,7 @@ uint8_t MCP9600::setThermocoupleType(Thermocouple_Type type){
 
 Thermocouple_Type MCP9600::getThermocoupleType(){
   uint8_t config = readSingleRegister(THERMO_SENSOR_CONFIG);
-  return (config >> 4); //clear the non-thermocouple-type bits in the config registe
+  return static_cast<Thermocouple_Type>(config >> 4); //clear the non-thermocouple-type bits in the config registe
 }
 
 uint8_t MCP9600::setFilterCoefficient(uint8_t coefficient){
@@ -475,6 +509,9 @@ bool MCP9600::isTempGreaterThanLimit(uint8_t number){
 /*------------------------- Internal I2C Abstraction ---------------- */
 
 uint8_t MCP9600::readSingleRegister(MCP9600_Register reg){
+  //Attempt to read the register until we exit with no error code
+  //This attempts to fix the bug where clock stretching sometimes failes, as
+  //described in the MCP9600 eratta
   for(uint8_t attempts; attempts <= retryAttempts; attempts++){
     _i2cPort->beginTransmission(DEV_ADDR);
     _i2cPort->write(reg);
@@ -487,6 +524,9 @@ uint8_t MCP9600::readSingleRegister(MCP9600_Register reg){
 }
 
 uint16_t MCP9600::readDoubleRegister(MCP9600_Register reg){
+  //Attempt to read the register until we exit with no error code
+  //This attempts to fix the bug where clock stretching sometimes failes, as
+  //described in the MCP9600 eratta
   for(byte attempts; attempts <= retryAttempts; attempts++){
     _i2cPort->beginTransmission(DEV_ADDR);
     _i2cPort->write(reg);

src/SparkFun_MCP9600.h

@@ -30,7 +30,7 @@ Distributed as-is; no warranty is given.
 #define retryAttempts 3 //how many times to attempt to read a register from the thermocouple before giving up
 
 // register pointers for various device functions
-enum MCP9600_Register {
+enum MCP9600_Register: uint8_t {
   HOT_JUNC_TEMP = 0x00,
   DELTA_JUNC_TEMP = 0x01,
   COLD_JUNC_TEMP = 0x02,
@@ -53,7 +53,7 @@ enum MCP9600_Register {
   DEVICE_ID = 0x20,
 };
 
-enum Thermocouple_Type {
+enum Thermocouple_Type: uint8_t {
   TYPE_K = 0b000,
   TYPE_J = 0b001,
   TYPE_T = 0b010,
@@ -64,19 +64,19 @@ enum Thermocouple_Type {
   TYPE_R = 0b111,
 };
 
-enum Ambient_Resolution {
-  RES_ZERO_POINT_0625 = 0b0,
-  RES_ZERO_POINT_25 = 0b1,
+enum Ambient_Resolution: bool {
+  RES_ZERO_POINT_0625 = 0,
+  RES_ZERO_POINT_25 = 1,
 };
 
-enum Thermocouple_Resolution {
+enum Thermocouple_Resolution: uint8_t {
   RES_18_BIT = 0b00,
   RES_16_BIT = 0b01,
   RES_14_BIT = 0b10,
   RES_12_BIT = 0b11,
 };
 
-enum Burst_Sample {
+enum Burst_Sample: uint8_t {
   SAMPLES_1 = 0b000,
   SAMPLES_2 = 0b001,
   SAMPLES_4 = 0b010,
@@ -87,7 +87,7 @@ enum Burst_Sample {
   SAMPLES_128 = 0b111,
 };
 
-enum Shutdown_Mode {
+enum Shutdown_Mode: uint8_t {
   NORMAL = 0x00,
   SHUTDOWN = 0x01,
   BURST = 0x02,
@@ -96,21 +96,20 @@ enum Shutdown_Mode {
 class MCP9600{
   public:
 
-  //Class constructor
-  MCP9600(uint8_t address = DEV_ADDR, TwoWire &wirePort = Wire);
-
   //Device status
+  bool begin(uint8_t address = DEV_ADDR, TwoWire &wirePort = Wire); //Sets device I2C address to a user-specified address, over whatever port the user specifies. 
+  bool available();                                                 //Returns true if the thermocouple (hot) junction temperature has been updated since we last checked. Also referred to as the data ready bit.
   bool isConnected();                                               //Returns true if the thermocouple will acknowledge over I2C, and false otherwise
   uint16_t deviceID();                                              //Returns the contents of the device ID register. The upper 8 bits are constant, but the lower contain revision data.
   bool checkDeviceID();                                             //Returns true if the constant upper 8 bits in the device ID register are what they should be according to the datasheet.
   bool resetToDefaults();                                           //Resets all device parameters to their default values. Returns 1 if there was an error, zero otherwise.
 
   //Sensor measurements
-  float getThermocoupleTemp(bool units = true);                     //Returns the thermocouple temperature. Set units to true for Celcius, or false for freedom units (Fahrenheit)
+  float getThermocoupleTemp(bool units = true);                     //Returns the thermocouple temperature, and clears the data ready bit. Set units to true for Celcius, or false for freedom units (Fahrenheit)
   float getAmbientTemp(bool units = true);                          //Returns the ambient (IC die) temperature. Set units to true for Celcius, or false for freedom units (Fahrenheit)
   float getTempDelta(bool units = true);                            //Returns the difference in temperature between the thermocouple and ambient junctions. Set units to true for Celcius, or false for freedom units (Fahrenheit)
-  signed long getRawADC();                                             //Returns the raw contents of the raw ADC register
-  bool isInputRangeExceeded();                                        //Returns true if the MCP9600's EMF range has been exceeded, and false otherwise.
+  signed long getRawADC();                                          //Returns the raw contents of the raw ADC register
+  bool isInputRangeExceeded();                                      //Returns true if the MCP9600's EMF range has been exceeded, and false otherwise.
 
   //Measurement configuration
   bool setAmbientResolution(Ambient_Resolution res);                //Changes the resolution on the cold (ambient) junction, for either 0.0625 or 0.25 degree C resolution. Lower resolution reduces conversion time.