BMP085.h

00001 // based on http://mbed.org/users/okini3939/code/BMP085/
00002 
00003 #ifndef BMP085_H
00004 #define BMP085_H
00005 
00006 #include "mbed.h"
00007 #include "I2C_Sensor.h"
00008 
00009 #define BMP085_I2C_ADDRESS 0xEE
00010 
00011 // register addresses
00012 #define BMP085_CAL_AC1           0xAA  // R   Calibration data (16 bits)
00013 #define BMP085_CAL_AC2           0xAC  // R   Calibration data (16 bits)
00014 #define BMP085_CAL_AC3           0xAE  // R   Calibration data (16 bits)    
00015 #define BMP085_CAL_AC4           0xB0  // R   Calibration data (16 bits)
00016 #define BMP085_CAL_AC5           0xB2  // R   Calibration data (16 bits)
00017 #define BMP085_CAL_AC6           0xB4  // R   Calibration data (16 bits)
00018 #define BMP085_CAL_B1            0xB6  // R   Calibration data (16 bits)
00019 #define BMP085_CAL_B2            0xB8  // R   Calibration data (16 bits)
00020 #define BMP085_CAL_MB            0xBA  // R   Calibration data (16 bits)
00021 #define BMP085_CAL_MC            0xBC  // R   Calibration data (16 bits)
00022 #define BMP085_CAL_MD            0xBE  // R   Calibration data (16 bits)
00023 #define BMP085_CONTROL           0xF4  // W   Control register 
00024 #define BMP085_CONTROL_OUTPUT    0xF6  // R   Output registers 0xF6=MSB, 0xF7=LSB, 0xF8=XLSB
00025 
00026 #define BMP085_SOFTRESET         0xE0  // -- unused registers
00027 #define BMP085_VERSION           0xD1  // ML_VERSION  pos=0 len=4 msk=0F  AL_VERSION pos=4 len=4 msk=f0
00028 #define BMP085_CHIPID            0xD0  // pos=0 mask=FF len=8 BMP085_CHIP_ID=0x55
00029 
00030 // BMP085 Modes
00031 #define MODE_ULTRA_LOW_POWER    0 //oversampling=0, internalsamples=1, maxconvtimepressure=4.5ms, avgcurrent=3uA, RMSnoise_hPA=0.06, RMSnoise_m=0.5
00032 #define MODE_STANDARD           1 //oversampling=1, internalsamples=2, maxconvtimepressure=7.5ms, avgcurrent=5uA, RMSnoise_hPA=0.05, RMSnoise_m=0.4
00033 #define MODE_HIGHRES            2 //oversampling=2, internalsamples=4, maxconvtimepressure=13.5ms, avgcurrent=7uA, RMSnoise_hPA=0.04, RMSnoise_m=0.3
00034 #define MODE_ULTRA_HIGHRES      3 //oversampling=3, internalsamples=8, maxconvtimepressure=25.5ms, avgcurrent=12uA, RMSnoise_hPA=0.03, RMSnoise_m=0.25
00035                   // "Sampling rate can be increased to 128 samples per second (standard mode) for
00036                   // dynamic measurement.In this case it is sufficient to measure temperature only 
00037                   // once per second and to use this value for all pressure measurements during period."
00038                   // (from BMP085 datasheet Rev1.2 page 10).
00039 // Control register
00040 #define READ_TEMPERATURE        0x2E 
00041 #define READ_PRESSURE           0x34 
00042 //Other
00043 #define MSLP                    101325          // Mean Sea Level Pressure = 1013.25 hPA (1hPa = 100Pa = 1mbar)
00044 
00045 class BMP085 : public I2C_Sensor {           
00046     public:
00047         BMP085(PinName sda, PinName scl);
00048         
00049         virtual void read();
00050         float Temperature, Pressure, Altitude;
00051          
00052     private:
00053         short AC1, AC2, AC3, B1, B2, MB, MC, MD; // calibration data
00054         unsigned short AC4, AC5, AC6;
00055         short oss;
00056         
00057         virtual void readraw();
00058 };
00059 
00060 #endif