th02.h

00001 // **********************************************************************************
00002 // Driver definition for HopeRF TH02 temperature and humidity sensor
00003 // **********************************************************************************
00004 // Creative Commons Attrib Share-Alike License
00005 // You are free to use/extend this library but please abide with the CC-BY-SA license:
00006 // http://creativecommons.org/licenses/by-sa/4.0/
00007 //
00008 // For any explanation see TH02 sensor information at
00009 // http://www.hoperf.com/sensor/app/TH02.htm
00010 //
00011 // Code based on following datasheet
00012 // http://www.hoperf.com/upload/sensor/TH02_V1.1.pdf 
00013 //
00014 // Written by Charles-Henri Hallard (http://hallard.me)
00015 //ported to mbed env by Philippe LAURENT (IUT de NICE France)
00016 //
00017 // History : V1.00 2014-07-14 - First release
00018 //           V1.10 2015-04-13 - changed to Wire library instead of I2C
00019 //
00020 // All text above must be included in any redistribution.
00021 //
00022 // **********************************************************************************
00023 #ifndef TH02_H
00024 #define TH02_H
00025 
00026 #include <mbed.h>            //
00027 
00028 // TH02 I2C Device address
00029 #define TH02_I2C_ADDR 0x40
00030 
00031 // TH02 Registers addresses
00032 #define TH02_STATUS 0
00033 #define TH02_DATAh  1
00034 #define TH02_DATAl  2
00035 #define TH02_CONFIG 3
00036 #define TH02_ID     17
00037 
00038 // TH02 custom error code return function
00039 #define TH02_I2C_ERR 0xFF
00040 
00041 // Unititialized values (arbitrary)
00042 #define TH02_UNINITIALIZED_TEMP 55555 // int32_t internal value 
00043 #define TH02_UNINITIALIZED_RH   1111  // int32_t internal value
00044 #define TH02_UNDEFINED_VALUE    12345 // int16_t returned value
00045 
00046 // we decide error if conversion is >= 50ms 
00047 #define TH02_CONVERSION_TIME_OUT  50
00048 
00049 // Bit definition of TH02 registers values
00050 #define TH02_STATUS_RDY    0x01
00051 
00052 #define TH02_CONFIG_START  0x01
00053 #define TH02_CONFIG_HEAT   0x02
00054 #define TH02_CONFIG_TEMP   0x10
00055 #define TH02_CONFIG_HUMI   0x00
00056 #define TH02_CONFIG_FAST   0x20
00057 
00058 // THO2 Linearization Coefficients
00059 #define TH02_A0   -4.7844
00060 #define TH02_A1    0.4008
00061 #define TH02_A2   -0.00393
00062 
00063 // TH02 Temperature compensation Linearization Coefficients
00064 #define TH02_Q0   0.1973
00065 #define TH02_Q1   0.00237
00066 
00067 
00068 
00069 
00070 
00071 class TH02 { 
00072   public:
00073             TH02(uint8_t address);
00074     uint8_t getId(uint8_t * pvalue);
00075     uint8_t getId(void);
00076     uint8_t getStatus(uint8_t * pvalue);
00077     bool isConverting(void);
00078     uint8_t waitEndConversion(void);
00079     uint8_t getConfig(uint8_t * pvalue);
00080     uint8_t setConfig(uint8_t config);
00081     uint8_t startTempConv(bool fastmode = false, bool heater = false);
00082     uint8_t startRHConv(bool fastmode = false, bool heater = false);
00083     int16_t roundInt(float value);
00084     int16_t getConversionValue(void);
00085     int16_t getConpensatedRH(bool round);
00086     int32_t getLastRawRH(void);
00087     int32_t getLastRawTemp(void);
00088 
00089 /**
00090   * TH02 constructor
00091   *
00092   * @param sda  I2C data pin
00093   * @param scl  I2C clock pin
00094   * @param address I2C slave sensor address
00095 
00096   */
00097   TH02(PinName sda, PinName scl, uint8_t address);
00098 
00099   /**
00100   * MFRC522 destructor
00101   */
00102   ~TH02();
00103 
00104 
00105 
00106   private:
00107 I2C             m_I2C;
00108     uint8_t writeCommand(uint8_t command, bool release=true);
00109     uint8_t writeRegister(uint8_t reg, uint8_t value);
00110     uint8_t readRegister(uint8_t reg, uint8_t * value);
00111 
00112     int32_t _last_temp; // Last measured temperature (for linearization)
00113     int32_t _last_rh;   // Last measured RH
00114     uint8_t _address;   // I2C Module Address
00115 
00116 
00117 
00118 };
00119 
00120   
00121 
00122 #endif