LSM303DLH.h

00001 #include "mbed.h"
00002 #include "vector.h"
00003 
00004 #include "LSM303DLH_RegisterDef.h"
00005 
00006 #ifndef M_PI
00007 #define M_PI 3.14159265358979323846
00008 #endif
00009 
00010 /** Tilt-compensated compass interface Library for the STMicro LSM303DLH 3-axis magnetometer, 3-axis acceleromter
00011  *
00012  * This file is subject to the terms and conditions of the GNU Lesser
00013  * General Public License v2.1. See the file LICENSE in the top level
00014  * directory for more details.
00015  *
00016  *
00017  *
00018  * Base on the @see doccumentation https://cdn-shop.adafruit.com/datasheets/LSM303DLHC.PDF
00019  * @code
00020  * #include "mbed.h"
00021  * #include "LSM303DLH.h"
00022  *
00023  * Serial debug(USBTX,USBRX);
00024  * LSM303DLH compass(p28, p27);
00025  *
00026  * int main() {
00027  *   float hdg;
00028  *   debug.format(8,Serial::None,1);
00029  *   debug.baud(115200);
00030  *   debug.printf("LSM303DLH Test\x0d\x0a");
00031  *   compass.setOffset(29.50, -0.50, 4.00); // example calibration
00032  *   compass.setScale(1.00, 1.03, 1.21);    // example calibration
00033  *   while(1) {
00034  *     hdg = compass.heading();
00035  *     debug.printf("Heading: %.2f\n", hdg);
00036  *     wait(0.1);
00037  *   }
00038  * }
00039  * @endcode 
00040  * 
00041  * @author Salco <JeSuisSalco@gmail.com>
00042  */
00043  
00044  /** enable for MSB @ lower address */
00045 //#define LSM303_LITLE_ENDIAN
00046 
00047 class LSM303DLH {
00048     public:
00049         /** Create a new interface for an LSM303DLH
00050          *
00051          * @param sda is the pin for the I2C SDA line
00052          * @param scl is the pin for the I2C SCL line
00053          */
00054         LSM303DLH(PinName sda, PinName scl);
00055         /** Create a new interface for an LSM303DLH
00056          *
00057          * @param ptrI2C is a pointer from existing I2C
00058          */
00059         LSM303DLH(I2C* ptrI2C);
00060         /** Destructor of the class
00061          */
00062         ~LSM303DLH();
00063         /** sets the x, y, and z offset corrections for hard iron calibration
00064          * 
00065          * Calibration details here:
00066          *  http://mbed.org/users/shimniok/notebook/quick-and-dirty-3d-compass-calibration/
00067          *
00068          * If you gather raw magnetometer data and find, for example, x is offset
00069          * by hard iron by -20 then pass +20 to this member function to correct
00070          * for hard iron.
00071          *
00072          * @param x is the offset correction for the x axis
00073          * @param y is the offset correction for the y axis
00074          * @param z is the offset correction for the z axis
00075          */
00076         void setOffset(float x, float y, float z);
00077         
00078         /** sets the scale factor for the x, y, and z axes
00079          *
00080          * Calibratio details here:
00081          *  http://mbed.org/users/shimniok/notebook/quick-and-dirty-3d-compass-calibration/
00082          *
00083          * Sensitivity of the three axes is never perfectly identical and this
00084          * function can help to correct differences in sensitivity.  You're
00085          * supplying a multipler such that x, y and z will be normalized to the
00086          * same max/min values
00087          */
00088         void setScale(float x, float y, float z);
00089 
00090         /** read the raw accelerometer and compass values
00091          *
00092          * @param a is the accelerometer 3d vector, written by the function
00093          * @param m is the magnetometer 3d vector, written by the function
00094          */
00095         bool read(vector &a, vector &m);
00096         /** read the raw accelerometer values
00097          *
00098          * @param a is the accelerometer 3d vector, written by the function
00099          */
00100         bool read_acc_raw(vector *a);
00101         /** read the raw compass values
00102          *
00103          * @param m is the magnetometer 3d vector, written by the function
00104          */
00105         bool read_mag_raw(vector *m);
00106         
00107         /** returns the magnetic heading with respect to the y axis
00108          *
00109          */
00110         float heading(void);
00111         
00112         /** returns the heading with respect to the specified vector
00113          *
00114          */
00115         float heading(vector from);
00116     
00117         /** sets the I2C bus frequency
00118          *
00119          * @param frequency is the I2C bus/clock frequency, either standard (100000) or fast (400000)
00120          */
00121         void frequency(int hz);
00122 
00123       private:
00124         enum DEV_ADDRS {
00125             /* --- Mag --- */
00126             addr_mag   = 0x3c,
00127             /* --- Acc --- */
00128             addr_acc   = 0x32,//0x30;
00129             };
00130         
00131         enum REG_ADDRS {
00132             /* --- Mag --- */
00133             CRA_REG_M   = 0x00,
00134             CRB_REG_M   = 0x01,
00135             MR_REG_M    = 0x02,
00136             OUT_X_M     = 0x03,
00137             OUT_Y_M     = 0x05,
00138             OUT_Z_M     = 0x07,
00139             SR_REG_M    = 0x09,
00140             /* --- Acc --- */
00141             CTRL_REG1_A = 0x20,
00142             CTRL_REG4_A = 0x23,
00143             STATUS_REG_A= 0x27,
00144             OUT_X_A     = 0x28,
00145             OUT_Y_A     = 0x2A,
00146             OUT_Z_A     = 0x2C,
00147         };
00148         
00149         I2C* m_ptr_I2C;//_compass;
00150         float _offset_x;
00151         float _offset_y;
00152         float _offset_z;
00153         float _scale_x;
00154         float _scale_y;
00155         float _scale_z;
00156         long _filt_ax;
00157         long _filt_ay;
00158         long _filt_az;
00159         int8_t m_FS;
00160         int8_t m_GN;
00161         bool m_have_createdI2C;
00162         void init(void) ;
00163         
00164         bool write_reg(int addr_i2c,int addr_reg, uint8_t v);
00165         bool write_reg(int addr_i2c,int addr_reg, char v);
00166         
00167         bool read_reg(int addr_i2c,int addr_reg, uint8_t *v);
00168         bool read_reg(int addr_i2c,int addr_reg, char *v);
00169         
00170         bool read_reg_short(int addr_i2c,int addr_reg, short *v);
00171         bool read_reg_short(DEV_ADDRS addr_i2c,REG_ADDRS addr_reg, OUT_XYZ_t *dataRead);
00172         
00173         int8_t get_FullScall_selection(void);
00174         float get_acc_value_in_g(OUT_XYZ_t* dataOut);
00175 };