Diff: lib_MAX31856.h

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0:9aa539a3d0f8

Child:

2:c5e7f83a00ed

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lib_MAX31856.h	Tue Jun 30 09:21:19 2020 +0000
@@ -0,0 +1,548 @@
+/******************************************************************//**
+* @file MAX31856.h
+*
+* @author Devin Alexander
+*
+* @version 1.0
+*
+* Started: SEPTEMBER 14th 2017
+*
+* Updated: 
+*
+* @brief Header file for MAX31856 class
+*
+***********************************************************************
+*
+* @copyright 
+* Copyright (C) 2017 Maxim Integrated Products, Inc., All Rights Reserved.
+*
+* Permission is hereby granted, free of charge, to any person obtaining a
+* copy of this software and associated documentation files (the "Software"),
+* to deal in the Software without restriction, including without limitation
+* the rights to use, copy, modify, merge, publish, distribute, sublicense,
+* and/or sell copies of the Software, and to permit persons to whom the
+* Software is furnished to do so, subject to the following conditions:
+*
+* The above copyright notice and this permission notice shall be included
+* in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
+* OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+* OTHER DEALINGS IN THE SOFTWARE.
+*
+* Except as contained in this notice, the name of Maxim Integrated
+* Products, Inc. shall not be used except as stated in the Maxim Integrated
+* Products, Inc. Branding Policy.
+*
+* The mere transfer of this software does not imply any licenses
+* of trade secrets, proprietary technology, copyrights, patents,
+* trademarks, maskwork rights, or any other form of intellectual
+* property whatsoever. Maxim Integrated Products, Inc. retains all
+* ownership rights.
+**********************************************************************/
+
+
+#ifndef MAX31856_h
+#define MAX31856_h
+#include "mbed.h"
+
+//*****************************************************************************
+//Define all the addresses of the registers in the MAX31856
+//*****************************************************************************
+#define ADDRESS_CR0_READ                   0x00         //Factory Default 00h
+#define ADDRESS_CR0_WRITE                  0x80
+#define ADDRESS_CR1_READ                   0x01         //Factory Default 03h
+#define ADDRESS_CR1_WRITE                  0x81
+#define ADDRESS_MASK_READ                  0x02         //Factory Default FFh
+#define ADDRESS_MASK_WRITE                 0x82
+#define ADDRESS_CJHF_READ                  0x03         //Factory Default 7Fh
+#define ADDRESS_CJHF_WRITE                 0x83
+#define ADDRESS_CJLF_READ                  0x04         //Factory Default C0h
+#define ADDRESS_CJLF_WRITE                 0x84
+#define ADDRESS_LTHFTH_READ                0x05         //Factory Default 7Fh
+#define ADDRESS_LTHFTH_WRITE               0x85
+#define ADDRESS_LTHFTL_READ                0x06         //Factory Default FFh
+#define ADDRESS_LTHFTL_WRITE               0x86
+#define ADDRESS_LTLFTH_READ                0x07         //Factory Default 80h
+#define ADDRESS_LTLFTH_WRITE               0x87
+#define ADDRESS_LTLFTL_READ                0x08         //Factory Default 00h
+#define ADDRESS_LTLFTL_WRITE               0x88
+#define ADDRESS_CJTO_READ                  0x09         //Factory Default 00h
+#define ADDRESS_CJTO_WRITE                 0x89
+#define ADDRESS_CJTH_READ                  0x0A         //Factory Default 00h
+#define ADDRESS_CJTH_WRITE                 0x8A
+#define ADDRESS_CJTL_READ                  0x0B         //Factory Default 00h
+#define ADDRESS_CJTL_WRITE                 0x8B
+#define ADDRESS_LTCBH_READ                 0x0C
+#define ADDRESS_LTCBM_READ                 0x0D
+#define ADDRESS_LTCBL_READ                 0x0E
+#define ADDRESS_SR_READ                    0x0F
+
+//*****************************************************************************    
+//Define parameters for control register zero (CR0)
+//*****************************************************************************    
+#define CR0_CONV_MODE_NORMALLY_OFF         0x00    //Power On Default value
+#define CR0_CONV_MODE_NORMALLY_ON          0x80
+
+#define CR0_1_SHOT_MODE_NO_CONVERSION      0x00    //defaults to this value
+#define CR0_1_SHOT_MODE_ONE_CONVERSION     0x40    //^
+
+#define CR0_OC_DETECT_DISABLED             0x00
+#define CR0_OC_DETECT_ENABLED_R_LESS_5k    0x10
+#define CR0_OC_DETECT_ENABLED_TC_LESS_2ms  0x20
+#define CR0_OC_DETECT_ENABLED_TC_MORE_2ms  0x30
+
+#define CR0_COLD_JUNC_ENABLE               0x00    //Power On Default value
+#define CR0_COLD_JUNC_DISABLE              0x08    //speed of conversion is sped up by 25ms when this optionis selected (Disable the cold junc)
+
+#define CR0_FAULT_MODE_COMPARATOR          0x00    //Power On Default value
+#define CR0_FAULT_MODE_INTERUPT            0x04 
+
+#define CR0_FAULTCLR_DEFAULT_VAL           0x00    //defaults to this value
+#define CR0_FAULTCLR_RETURN_FAULTS_TO_ZERO 0x02    //^
+
+#define CR0_FILTER_OUT_60Hz                0x00    //Preset value
+#define CR0_FILTER_OUT_50Hz                0x01    //^
+
+
+//*****************************************************************************    
+//Define parameters for control register one (CR1)
+//*****************************************************************************    
+#define CR1_AVG_TC_SAMPLES_1               0x00    //Power on default value
+#define CR1_AVG_TC_SAMPLES_2               0x10
+#define CR1_AVG_TC_SAMPLES_4               0x20
+#define CR1_AVG_TC_SAMPLES_8               0x30
+#define CR1_AVG_TC_SAMPLES_16              0x40
+
+// Define which type of thermocouple the MAX31856 is using. This is for lineariztion purposes
+#define CR1_TC_TYPE_B                      0x00
+#define CR1_TC_TYPE_E                      0x01
+#define CR1_TC_TYPE_J                      0x02
+#define CR1_TC_TYPE_K                      0x03         //Power on default value
+#define CR1_TC_TYPE_N                      0x04
+#define CR1_TC_TYPE_R                      0x05
+#define CR1_TC_TYPE_S                      0x06
+#define CR1_TC_TYPE_T                      0x07
+#define CR1_TC_TYPE_VOLT_MODE_GAIN_8       0x08
+#define CR1_TC_TYPE_VOLT_MODE_GAIN_32      0x0C
+
+//*****************************************************************************    
+//Define parameters for the mask register (MASK)
+//*****************************************************************************    
+#define MASK_CJ_FAULT_THRESHOLD_HIGH       0x20
+#define MASK_CJ_FAULT_THRESHOLD_LOW        0x10
+#define MASK_TC_FAULT_THRESHOLD_HIGH       0x08
+#define MASK_TC_FAULT_THRESHOLD_LOW        0x04
+#define MASK_OVER_UNDER_VOLT_FAULT         0x02
+#define MASK_OPEN_CIRCUIT_FAULT            0x01
+
+//*****************************************************************************    
+//If these defined values are &= (bitwise ANDed) with the contents of a register, it will reset the bits pertaing to the specific bitfields to zero
+//*****************************************************************************    
+#define CR0_CLEAR_BITS_7                   ~(0x80)
+#define CR0_CLEAR_BITS_6                   ~(0x40)
+#define CR0_CLEAR_BITS_5_4                 ~(0x30)
+#define CR0_CLEAR_BITS_3                   ~(0x08)
+#define CR0_CLEAR_BITS_2                   ~(0x04)
+#define CR0_CLEAR_BITS_1                   ~(0x02)
+#define CR0_CLEAR_BITS_0                   ~(0x01)
+
+#define CR1_CLEAR_BITS_6_4                 ~(0x70)
+#define CR1_CLEAR_BITS_3_0                 ~(0x0F)
+
+#define MASK_CLEAR_BITS_5                  ~(0x20)
+#define MASK_CLEAR_BITS_4                  ~(0x10)
+#define MASK_CLEAR_BITS_3                  ~(0x08)
+#define MASK_CLEAR_BITS_2                  ~(0x04)
+#define MASK_CLEAR_BITS_1                  ~(0x02)
+#define MASK_CLEAR_BITS_0                  ~(0x01)
+
+//*****************************************************************************   
+///Parameters that are used throughout the library
+//*****************************************************************************   
+#define TC_MAX_VAL_FAULT                   1800
+#define TC_MIN_VAL_FAULT                   -210
+#define CJ_MAX_VAL_FAULT                   125
+#define CJ_MIN_VAL_FAULT                   -55
+
+
+
+/**
+ * @brief Library for the MAX31856\n
+ * The MAX31856 thermocouple temperature sensor accurately measures temperature 
+ * and provides a vast amount of features such as:
+ * //FEATURE 
+ * //FEATURE
+ * //FEATURE
+ * //FEATURE
+ * //FEATURE
+*  //FEATURE
+ * Communication is through an SPI-compatible interface.
+ *
+ * @code
+ * #include "mbed.h"
+ * #include "MAX31856.h"
+ * 
+ *
+ * // Hardware serial port 
+ * Serial serial(USBTX, USBRX);
+ * 
+ * //SPI communications
+ * SPI spi(SPIO MOSI,SPIO MISO,SPIO SCK);
+ * 
+ * //Thermocouples
+ * MAX31856 Thermocouple1(spi, CHIPSELECT);
+ * 
+ * 
+ * int main(void) 
+ * {
+ *      float temperature_TC_1, temperature_CJ_1;
+ *      while(true)
+ *      {
+ *          temperature_TC_1=Thermocouple1.readTC();
+ *          temperature_CJ_1=Thermocouple1.readCJ();
+ *          serial.printf("MAX31856 TC = %f Celsius   MAX31856 CJ = %f Celsius  \n\r",temperature_TC_1,temperature_CJ_1);
+ *          wait(1.0);
+ *      }
+ * }
+ * @endcode
+ */
+
+
+
+/** Please see pages 18-26 in the MAX31856 data sheet to see what register bit masks are needed to be set 
+to achieve functionality desired. The data sheet can be found at 
+            
+           ***     https://datasheets.maximintegrated.com/en/ds/MAX31856.pdf      ***
+*/
+
+
+/**
+* MAX31856 Class
+*/
+class MAX31856
+{
+
+public:
+//*****************************************************************************    
+//Constructor and Destructor for the class
+//***************************************************************************** 
+    /**
+    * @brief Constructor to create MAX31856 object with SPI information as well as preconfiguration parameter settings in configuration registers Zero and One
+    * @param _spi - Reference to SPI object
+    * @param _ncs - Chip Select for SPI comunications with the oject
+    * @param _type - Type of thermocouple used
+    * @param _fltr - Feature of the MAX31856 to filter out either 50Hz/60Hz from signal
+    * @param _samples - How many samples are averaged for one conversion
+    * @param _conversion_mode - Choose between always on and making conversions and off in between requests for a reading
+    */
+    MAX31856(SPI& _spi, PinName _ncs, uint8_t _type=CR1_TC_TYPE_K, uint8_t _fltr=CR0_FILTER_OUT_60Hz, uint8_t _samples=CR1_AVG_TC_SAMPLES_1, uint8_t _conversion_mode=CR0_CONV_MODE_NORMALLY_OFF); 
+    
+    
+    /** @brief Destructor */
+    ~MAX31856(void);
+    
+    
+//*****************************************************************************    
+//Temperature Functions
+//***************************************************************************** 
+    /** 
+    * @brief  Requests read of the thermocouple temperature
+    * @return float of the converted thermocouple reading based on current configurations
+    */
+    float readTC();
+    
+    
+    /** 
+    * @brief  Requests read of the cold junction temperature
+    * @return float of the converted artificial cold junction reading based on current configurations
+    */
+    float readCJ();
+
+    
+//*****************************************************************************    
+//Functions for register CR0
+//*****************************************************************************
+    /** 
+    * @brief  Sets bits in the configuration register zero for setting the rate of conversions
+    * @param val    \li  CR0_CONV_MODE_NORMALLY_OFF      (Power On Default value)
+    *               \li  CR0_CONV_MODE_NORMALLY_ON 
+    * @return       \li 1 on success   
+    *               \li 0 if there is an incorrect parameter that is passed in as parameter val
+    */
+    bool setConversionMode(uint8_t val);
+    
+    
+    /** 
+    * @brief  Sets bits in the configuration register zero for enabling one conversion to take place
+    * @param val    \li   CR0_1_SHOT_MODE_NO_CONVERSION      (Power On Default value)
+    *               \li   CR0_1_SHOT_MODE_ONE_CONVERSION      (This bit self clears itself to default back to CR0_1_SHOT_MODE_NO_CONVERSION after singular conversion takes place)
+    * @return       \li 1 on success   
+    *               \li 0 if there is an incorrect parameter that is passed in as parameter val
+    */
+    bool setOneShotMode(uint8_t val);
+    
+    
+    /** 
+    * @brief  Sets bits in the configuration register zero for configuring open circuit fault detection
+    * @param val    \li   CR0_OC_DETECT_DISABLED      (Power On Default value)
+    *               \li   CR0_OC_DETECT_ENABLED_R_LESS_5k
+    *               \li   CR0_OC_DETECT_ENABLED_TC_LESS_2ms
+    *               \li   CR0_OC_DETECT_ENABLED_TC_MORE_2ms
+    * @return       \li 1 on success   
+    *               \li 0 if there is an incorrect parameter that is passed in as parameter val
+    */
+    bool setOpenCircuitFaultDetection(uint8_t val);
+    
+    
+    /** 
+    * @brief  Sets bits in the configuration register zero for disabling or enabling the Cold Junction
+    * @param val    \li   CR0_COLD_JUNC_ENABLE      (Power On Default value)
+    *               \li   CR0_COLD_JUNC_DISABLE
+    * @return       \li 1 on success   
+    *               \li 0 if there is an incorrect parameter that is passed in as parameter val
+    */
+    bool setColdJunctionDisable(uint8_t val);
+    
+    
+    /** 
+    * @brief  Sets bits in the configuration register zero for setting fault mode status
+    * @param val    \li   CR0_FAULT_MODE_COMPARATOR      (Power On Default value)
+    *               \li   CR0_FAULT_MODE_INTERUPT
+    * @return       \li 1 on success   
+    *               \li 0 if there is an incorrect parameter that is passed in as parameter val
+    */
+    bool setFaultMode(uint8_t val);
+    
+    
+    /** 
+    * @brief  Sets bits in the configuration register zero for clearing fault status
+    * @param val    \li   CR0_FAULTCLR_DEFAULT_VAL      (Power On Default value)
+    *               \li   CR0_FAULTCLR_RETURN_FAULTS_TO_ZERO      (This bit self clears itself to default back to CR0_FAULTCLR_DEFAULT_VAL after fault status is cleared)
+    * @return       \li 1 on success   
+    *               \li 0 if there is an incorrect parameter that is passed in as parameter val
+    */
+    bool setFaultStatusClear(uint8_t val);
+    
+    
+    /** 
+    * @brief  Sets bits in the configuration register zero for setting which of the two filter modes either 50Hz or 60Hz cancelation
+    * @param val    \li   CR0_FILTER_OUT_60Hz      (Power On Default value)
+    *               \li   CR0_FILTER_OUT_50Hz
+    * @return       \li 1 on success   
+    *               \li 0 if there is an incorrect parameter that is passed in as parameter val
+    */
+    bool setEmiFilterFreq(uint8_t val);
+    
+    
+//*****************************************************************************    
+//Functions for register CR1
+//*****************************************************************************
+    /** 
+    * @brief  Sets bits in the configuration register one for setting how many readings are taken 
+    * @param val    \li   CR1_AVG_TC_SAMPLES_1      (Power On Default value)
+    *               \li   CR1_AVG_TC_SAMPLES_2
+    *               \li   CR1_AVG_TC_SAMPLES_4
+    *               \li   CR1_AVG_TC_SAMPLES_8
+    *               \li   CR1_AVG_TC_SAMPLES_16
+    * @return       \li 1 on success   
+    *               \li 0 if there is an incorrect parameter that is passed in as parameter val
+    */
+    bool setNumSamplesAvg(uint8_t val);
+    
+    
+    /** 
+    * @brief  Sets bits in the configuration register one for setting which thermocouple type is going to be programmed into the MAX31856 for linearization of thermovoltage produced and temperature
+    * @param val    \li   CR1_TC_TYPE_B
+    *               \li   CR1_TC_TYPE_E
+    *               \li   CR1_TC_TYPE_J
+    *               \li   CR1_TC_TYPE_K      (Power On Default value)
+    *               \li   CR1_TC_TYPE_N
+    *               \li   CR1_TC_TYPE_R
+    *               \li   CR1_TC_TYPE_S
+    *               \li   CR1_TC_TYPE_T
+    *               \li   CR1_TC_TYPE_VOLT_MODE_GAIN_8
+    *               \li   CR1_TC_TYPE_VOLT_MODE_GAIN_32
+    * @return       \li 1 on success   
+    *               \li 0 if there is an incorrect parameter that is passed in as parameter val
+    */
+    bool setThermocoupleType(uint8_t val);
+    
+
+//*****************************************************************************    
+//Functions for register MASK
+//*****************************************************************************    
+    /** 
+    * @brief  Sets bits in the configuration register one for setting fault masks
+    * @param val    \li   MASK_CJ_FAULT_THRESHOLD_HIGH
+    *               \li   MASK_CJ_FAULT_THRESHOLD_LOW
+    *               \li   MASK_TC_FAULT_THRESHOLD_HIGH
+    *               \li   MASK_TC_FAULT_THRESHOLD_LOW
+    *               \li   MASK_OVER_UNDER_VOLT_FAULT
+    *               \li   MASK_OPEN_CIRCUIT_FAULT
+    * @param enable \li  0 for disabling the mask in whichever option is selcted in parameter val
+    *               \li  1 for enabling the mask in whichever option is selcted in parameter val
+    * @return       \li 1 on success   
+    *               \li 0 if there is an incorrect parameter that is passed in as parameter val
+    */
+    bool setFaultMasks(uint8_t val, bool enable);
+    
+    
+    /** 
+    * @brief  Sets bits in the configuration register one for setting thresholds that corespond to the fault mask settings
+    * @param val    \li   MASK_CJ_FAULT_THRESHOLD_HIGH
+    *               \li   MASK_CJ_FAULT_THRESHOLD_LOW
+    *               \li   MASK_TC_FAULT_THRESHOLD_HIGH
+    *               \li   MASK_TC_FAULT_THRESHOLD_LOW
+    * @param temperature value that you want to program into a threshold register for temperatre
+    * @return return value that was programmed into the threshold register 
+    */
+    bool setFaultThresholds(uint8_t val, float temperature);
+
+
+//*****************************************************************************    
+//Check Fault Status Functions
+//*****************************************************************************    
+    /** 
+    * @brief  Check the fault stautus register to see if there is anything wrong with range of thermocouple temperature 
+    *         whether outside opperating temperatures or if above/below thresholds that are set
+    * @return       \li 0 if no faults are present
+    *               \li 1 if Thermocouple temp is higher than the threshold 
+    *               \li 2 if Thermocouple temp is lower  than the threshold 
+    *               \li 3 if Thermocouple temp is outside operating range of termocouple type
+    *               \li 4 if Thermocouple temp is higher than the threshold && is outside operating range of termocouple type
+    *               \li 5 if Thermocouple temp is lower  than the threshold && is outside operating range of termocouple type
+    */
+    uint8_t checkFaultsThermocoupleThresholds();
+    
+    
+    /** 
+    * @brief  Check the fault stautus register to see if there is anything wrong with range of cold junction temperature 
+    *         whether outside opperating temperatures or if above/below thresholds that are set
+    * @return       \li 0 if no faults are present
+    *               \li 1 if Cold Junction temp is higher than the threshold 
+    *               \li 2 if Cold Junction temp is lower  than the threshold 
+    *               \li 3 if Cold Junction temp is outside operating range of termocouple type
+    *               \li 4 if Cold Junction temp is higher than the threshold && is outside operating range of termocouple type
+    *               \li 5 if Cold Junction temp is lower  than the threshold && is outside operating range of termocouple type
+    */
+    uint8_t checkFaultsColdJunctionThresholds();
+    
+    
+    /** 
+    * @brief  Check the fault stautus register to see if there is anything wrong with thermocouple connection to the MAX31856
+    * @return       \li 1 if no faults are present
+    *               \li 0 if there is a fault and there needs to be information printed to the console to help diagnose issues
+    */
+    bool checkFaultsThermocoupleConnection();
+    
+    
+//*****************************************************************************    
+//General Functions
+//*****************************************************************************    
+    /**
+    * @brief This function is to read current contents of register, manipulate the contents, then rewrite the specific register\n
+    *               \li Read the value of a register from contents of register matching the parameter read_address
+    *               \li Clear the bits needed to be changed by bitwise ANDing the read value with the 8 bit parameter clear_bits
+    *               \li Set the bits of interest in the 8 bit value by bitwise ORing the value from step two with parameter val
+    *               \li Rewrite to the register with the new 8 bit value to the register with the address with parameter write_address
+    * @param read_address - Address of register to read the data before it's changed
+    * @param write_address - Address of register to rewrite the changed data
+    * @param clear_bits - Parameter that is 
+    * @param val - Bitfield that contains bits related to function specific settings
+    * @return       \li 1 on success
+    */
+    bool registerReadWriteByte(uint8_t read_address, uint8_t write_address, int clear_bits, uint8_t val);
+    
+    
+    /**
+    * @brief This function is to read current contents of register, manipulate the contents, then rewrite the specific register\n
+    *               \li Read the value of a register from contents of register matching the parameter read_address
+    *               \li Clear the bits needed to be changed by bitwise ANDing the read value with the 8 bit parameter clear_bits
+    *               \li Set the bits of interest in the 8 bit value by bitwise ORing the value from step two with parameter val
+    *               \li Write to the register with the new 8 bit value to the register with the address with parameter write_address    
+    * @param write_address - Address of register to rewrite the changed data
+    * @param val - Byte of information that is going to be written to the regitser with the address that matches the parameter write_address
+    * @return   \li 1 on success
+    */
+    bool registerWriteByte(uint8_t write_address, uint8_t val);
+    
+    
+    /**
+    * @brief This function is to read current contents of register by passing in the address of the read address and return contents of the register   
+    * @param read_address - Address of register to read data from
+    * @return   \li byte contained in the address
+    */
+    uint8_t registerReadByte(uint8_t read_address);
+    
+    
+    /**
+    * @brief This function is to read current contents of register by passing in the address of the read address and return contents of the register   
+    * @param temperature - Float of value to offest the value of the cold junction offset by (must be between -8°C to +7.9375°C)
+    * @return   \li 1 on successfully updated coldjunction offset
+    *           \li 0 if parameter temperature does not fall between range -8°C to +7.9375°C
+    */
+    bool coldJunctionOffset(float temperature);
+    
+
+private:
+
+//*****************************************************************************    
+//Private Functions
+//*****************************************************************************    
+    /** @brief  Writes the chip seleect pin low to begin SPI communications */
+    void spiEnable();
+    
+    
+    /** @brief  Writes the chip seleect pin high to end SPI communications */
+    void spiDisable();
+    
+    /** @brief  Calculates minimum wait time for a conversion to take place */
+    void calculateDelayTime();
+       
+    
+//*****************************************************************************    
+//Private Members
+//*****************************************************************************        
+    /// SPI object
+    SPI& spi;
+    
+    /// Chip select pin for SPI communications
+    DigitalOut ncs;
+    
+    /// Number of samples the thermocouple is configured to average
+    uint8_t samples;
+    
+    /// 0=thermocouple is set to one of 8 thermocouple types   and   1=Thermocouple is configured to report in voltage mode
+    bool voltage_mode;
+    
+    /// 0=60Hz   and   1=50Hz
+    bool filter_mode;
+    
+    /// 0=MAX31856 is off, so no conversion is taking place currently   and   1=Always On and converting
+    bool conversion_mode;
+    
+    /// 0=cold junction is disabled   and   1=cold junction is enabled
+    bool cold_junction_enabled;
+    
+    ///Define a return val for all boolean functions
+    bool return_val;
+    
+    ///Used to figure out when a new conversion is ready to go
+    uint32_t lastReadTime;
+    
+    ///How many conversions have taken place since conversion mode was switched into auto mode
+    ///Also this value should be 0 if the mode is in oneshot mode
+    uint32_t thermocouple_conversion_count; 
+    
+    ///time in milliseconds that is needed minimum for a new conversion to take place
+    uint32_t conversion_time;
+
+    float prev_TC;
+};
+
+#endif  /* __MAX31856_H_ */