BME280.h

00001 #ifndef _BME280_H_
00002 #define _BME280_H_
00003 #include "mbed.h"
00004 
00005 typedef int32_t  BME280_S32_t ;
00006 typedef uint32_t BME280_U32_t ;
00007 typedef long long signed int BME280_S64_t ;
00008 
00009 #if 0
00010 #define BME280_U32_t uint32_t
00011 #define BME280_S32_t int32_t
00012 #define BME280_S64_t int64_t
00013 #endif 
00014 
00015 /**
00016  * BME280 Environmental sensor
00017  *
00018  * @note Note: Interface selection is done by the value of CSB (chip select)
00019  * @note if CSB is pulled-up, I2C interface is active.
00020  * @note if CSB is pulled-down, SPI interface is active.
00021  * @note After CSB has been pulled down once (regardless of whether any clock cycle occurred)
00022  * @note the I2C interface is disabled until the next power-on-reset.
00023  */
00024 
00025 class BME280
00026 {
00027 public:
00028  /**
00029   * BME280 I2C Interface
00030   *
00031   * @param sda SDA pin
00032   * @param scl SCL pin
00033   * @param addr address of the I2C peripheral
00034   */
00035 BME280(PinName sda, PinName scl, int addr) ;
00036 
00037  /**
00038   * BME280 SPI Interface
00039   *
00040   * @param sck  SPI SCKL pin
00041   * @param miso SPI Master In Slave Out pin
00042   * @param mosi SPI Master Out Slave In pin
00043   * @param cs   SPI Chip Select pin
00044   */
00045 BME280(PinName sck, PinName miso, PinName mosi, PinName cs) ;
00046 
00047 /**
00048  * BME280 destructor
00049  */
00050 ~BME280() ;
00051 
00052 /** 
00053  * software reset
00054  *
00055  * @param none
00056  * @returns none
00057  */
00058 void reset(void) ; 
00059 
00060 /**
00061  * initialization
00062  *
00063  * @param none
00064  * @reurns none
00065  */
00066 void init(void) ;
00067 
00068 /**
00069  * trigger for one-shot measure
00070  *
00071  * @param none
00072  * @returns none
00073  */
00074 void trigger(void) ; 
00075 
00076 /**
00077  * check status register for the device activity
00078  *
00079  * @param none
00080  * @returns uint8_t measuring (0x08) or in NVM udpate (0x01)
00081  */
00082 uint8_t  busy(void) ;
00083 
00084 /**
00085  * get device ID
00086  *
00087  * @param none
00088  * @returns uint8_t ID for BME280 0x60
00089  */
00090 uint8_t getID(void) ;
00091 
00092 /**
00093  * get Temperature
00094  *
00095  * @param none
00096  * @returns float temperature in degree Celsious
00097  */
00098 float getTemperature(void) ;
00099 
00100 /**
00101  * get Humidity
00102  *
00103  * @param none
00104  * @returns float humidity in %
00105  */
00106 float getHumidity(void) ;
00107 
00108 /**
00109  * get Pressure
00110  *
00111  * @param none
00112  * @returns float pressure in hPa
00113  */
00114 float getPressure(void) ;
00115 
00116 private:
00117   SPI *m_spi ;
00118   I2C *m_i2c ;
00119   DigitalOut *m_cs ;
00120   int m_addr ;
00121   BME280_S32_t t_fine ;
00122   
00123   uint16_t dig_T1 ;
00124   int16_t  dig_T2 ;
00125   int16_t  dig_T3 ;
00126   uint16_t dig_P1 ; 
00127   int16_t  dig_P2 ;
00128   int16_t  dig_P3 ; 
00129   int16_t  dig_P4 ;
00130   int16_t  dig_P5 ;
00131   int16_t  dig_P6 ; 
00132   int16_t  dig_P7 ;
00133   int16_t  dig_P8 ;
00134   int16_t  dig_P9 ;
00135   uint8_t  dig_H1 ;
00136   int16_t  dig_H2 ;
00137   uint8_t  dig_H3 ;
00138   int16_t  dig_H4 ;
00139   int16_t  dig_H5 ; 
00140   int8_t   dig_H6 ;
00141 
00142   void i2c_readRegs(int addr, uint8_t *data, int len) ;
00143   void i2c_writeRegs(uint8_t *data, int len) ;
00144   void spi_readRegs(int addr, uint8_t *data, int len) ;
00145   void spi_writeRegs(uint8_t *data, int len) ;
00146   void readRegs(int addr, uint8_t *data, int len) ;
00147   void writeRegs(uint8_t *data, int len) ;
00148 } ;
00149 #endif /* _BME280_H_ */