LPS.h

00001 #ifndef LPS_h
00002 #define LPS_h
00003 
00004 #include "mbed.h" // for int8_t data type
00005 
00006 class LPS
00007 {
00008   public:
00009     enum deviceType { device_331AP, device_25H, device_auto };
00010     enum sa0State { sa0_low, sa0_high, sa0_auto };
00011 
00012     // register addresses
00013     // Note: where register names differ between the register mapping table and
00014     // the register descriptions in the datasheets, the names from the register
00015     // descriptions are used here.
00016     enum regAddr
00017     {
00018       REF_P_XL                = 0x08,
00019       REF_P_L                 = 0x09,
00020       REF_P_H                 = 0x0A,
00021                               
00022       WHO_AM_I                = 0x0F,
00023                               
00024       RES_CONF                = 0x10,
00025                               
00026       CTRL_REG1               = 0x20,
00027       CTRL_REG2               = 0x21,
00028       CTRL_REG3               = 0x22,
00029       CTRL_REG4               = 0x23, // 25H
00030               
00031       STATUS_REG              = 0x27,
00032                             
00033       PRESS_OUT_XL            = 0x28,
00034       PRESS_OUT_L             = 0x29,
00035       PRESS_OUT_H             = 0x2A,
00036 
00037       TEMP_OUT_L              = 0x2B,
00038       TEMP_OUT_H              = 0x2C,
00039       
00040       FIFO_CTRL               = 0x2E, // 25H
00041       FIFO_STATUS             = 0x2F, // 25H
00042       
00043       AMP_CTRL                = 0x30, // 331AP
00044       
00045       RPDS_L                  = 0x39, // 25H
00046       RPDS_H                  = 0x3A, // 25H
00047       
00048       DELTA_PRESS_XL          = 0x3C, // 331AP
00049       DELTA_PRESS_L           = 0x3D, // 331AP
00050       DELTA_PRESS_H           = 0x3E, // 331AP
00051       
00052       
00053       // dummy addresses for registers in different locations on different devices;
00054       // the library translates these based on device type
00055       // value with sign flipped is used as index into translated_regs array
00056     
00057       INTERRUPT_CFG    = -1,
00058       INT_SOURCE       = -2,
00059       THS_P_L          = -3,
00060       THS_P_H          = -4,
00061       // update dummy_reg_count if registers are added here!
00062       
00063       
00064       // device-specific register addresses
00065       
00066       LPS331AP_INTERRUPT_CFG  = 0x23,
00067       LPS331AP_INT_SOURCE     = 0x24,
00068       LPS331AP_THS_P_L        = 0x25,
00069       LPS331AP_THS_P_H        = 0x26,
00070       
00071       LPS25H_INTERRUPT_CFG    = 0x24,
00072       LPS25H_INT_SOURCE       = 0x25,
00073       LPS25H_THS_P_L          = 0x30,
00074       LPS25H_THS_P_H          = 0x31,
00075     };
00076 
00077     LPS(I2C& p_i2c);
00078 
00079     bool init(deviceType device = device_auto,uint8_t sa0 = sa0_auto);
00080     deviceType getDeviceType(void) { return _device; }
00081     int8_t getAddress(void) { return address; }
00082 
00083     void enableDefault(void);
00084 
00085     void writeReg(char reg, char value);
00086     int8_t readReg(char reg);
00087 
00088     float readPressureMillibars(void);
00089     float readPressureInchesHg(void);
00090     int32_t readPressureRaw(void);
00091     float readTemperatureC(void);
00092     float readTemperatureF(void);
00093     int16_t readTemperatureRaw(void);
00094 
00095     static float pressureToAltitudeMeters(double pressure_mbar, double altimeter_setting_mbar = 1013.25);
00096     static float pressureToAltitudeFeet(double pressure_inHg, double altimeter_setting_inHg = 29.9213);
00097 
00098   private:
00099     deviceType _device; // chip type (331AP or 25H)
00100     I2C &_i2c;
00101     uint8_t address;
00102     
00103     static const int dummy_reg_count = 4;
00104     regAddr translated_regs[dummy_reg_count + 1]; // index 0 not used
00105 
00106     bool detectDeviceAndAddress(deviceType device, sa0State sa0);
00107     bool detectDevice(deviceType device);
00108     int testWhoAmI(uint8_t address);
00109 };
00110 
00111 #endif