LSM303DLM.h

00001 #ifndef __LSM303DLM_H
00002 #define __LSM303DLM_H
00003 
00004 #include "mbed.h"
00005 
00006 // register addresses
00007 
00008 #define CTRL_REG1_A       0x20
00009 #define CTRL_REG2_A       0x21
00010 #define CTRL_REG3_A       0x22
00011 #define CTRL_REG4_A       0x23
00012 #define CTRL_REG5_A       0x24
00013 #define CTRL_REG6_A       0x25 // DLHC only
00014 #define HP_FILTER_RESET_A 0x25 // DLH, DLM only
00015 #define REFERENCE_A       0x26
00016 #define STATUS_REG_A      0x27
00017 
00018 #define OUT_X_L_A         0x28
00019 #define OUT_X_H_A         0x29
00020 #define OUT_Y_L_A         0x2A
00021 #define OUT_Y_H_A         0x2B
00022 #define OUT_Z_L_A         0x2C
00023 #define OUT_Z_H_A         0x2D
00024 
00025 #define INT1_CFG_A        0x30
00026 #define INT1_SRC_A        0x31
00027 #define INT1_THS_A        0x32
00028 #define INT1_DURATION_A   0x33
00029 #define INT2_CFG_A        0x34
00030 #define INT2_SRC_A        0x35
00031 #define INT2_THS_A        0x36
00032 #define INT2_DURATION_A   0x37
00033 
00034 #define CRA_REG_M         0x00
00035 #define CRB_REG_M         0x01
00036 #define MR_REG_M          0x02
00037 
00038 #define OUT_X_H_M         0x03
00039 #define OUT_X_L_M         0x04
00040 #define OUT_Y_H_M         0x07
00041 #define OUT_Y_L_M         0x08
00042 #define OUT_Z_H_M         0x05
00043 #define OUT_Z_L_M         0x06
00044 
00045 #define SR_REG_M          0x09
00046 #define IRA_REG_M         0x0A
00047 #define IRB_REG_M         0x0B
00048 #define IRC_REG_M         0x0C
00049 
00050 #define WHO_AM_I_M        0x0F
00051 
00052 #define OUT_Z_H_M         0x05
00053 #define OUT_Z_L_M         0x06
00054 #define OUT_Y_H_M         0x07
00055 #define OUT_Y_L_M         0x08
00056 
00057 /** Tilt-compensated compass interface Library for the STMicro LSM303DLm 3-axis magnetometer, 3-axis acceleromter
00058  * @author Michael Shimniok http://www.bot-thoughts.com/
00059  *
00060  * This is an early revision; I've not yet implemented heading calculation and the interface differs from my
00061  * earlier LSM303DLH; I hope to make this library drop in compatible at some point in the future.
00062  * setScale() and setOffset() have no effect at this time.
00063  *
00064  * @code
00065  * #include "mbed.h"
00066  * #include "LSM303DLM.h"
00067  *
00068  * LSM303DLM compass(p28, p27);
00069  * ...
00070  * int a[3], m[3];
00071  * ...
00072  * compass.readAcc(a);
00073  * compass.readMag(m);
00074  *
00075  * @endcode
00076  */
00077 class LSM303DLM {
00078 
00079     public:
00080         /** Create a new interface for an LSM303DLM
00081          *
00082          * @param sda is the pin for the I2C SDA line
00083          * @param scl is the pin for the I2C SCL line
00084          */
00085         LSM303DLM(PinName sda, PinName scl);
00086 
00087         /** sets the x, y, and z offset corrections for hard iron calibration
00088          * 
00089          * Calibration details here:
00090          *  http://mbed.org/users/shimniok/notebook/quick-and-dirty-3d-compass-calibration/
00091          *
00092          * If you gather raw magnetometer data and find, for example, x is offset
00093          * by hard iron by -20 then pass +20 to this member function to correct
00094          * for hard iron.
00095          *
00096          * @param x is the offset correction for the x axis
00097          * @param y is the offset correction for the y axis
00098          * @param z is the offset correction for the z axis
00099          */
00100         void setOffset(float x, float y, float z);
00101         
00102         /** sets the scale factor for the x, y, and z axes
00103          *
00104          * Calibratio details here:
00105          *  http://mbed.org/users/shimniok/notebook/quick-and-dirty-3d-compass-calibration/
00106          *
00107          * Sensitivity of the three axes is never perfectly identical and this
00108          * function can help to correct differences in sensitivity.  You're
00109          * supplying a multipler such that x, y and z will be normalized to the
00110          * same max/min values
00111          */
00112         void setScale(float x, float y, float z);
00113 
00114         /** read the calibrated accelerometer and magnetometer values
00115          *
00116          * @param a is the accelerometer 3d vector, written by the function
00117          * @param m is the magnetometer 3d vector, written by the function
00118          */
00119         void read(int a[3], int m[3]);
00120         
00121         /** read the calibrated accelerometer values
00122          *
00123          * @param a is the accelerometer 3d vector, written by the function
00124          */
00125         void readAcc(int a[3]);
00126 
00127         /** read the calibrated magnetometer values
00128          *
00129          * @param m is the magnetometer 3d vector, written by the function
00130          */
00131         void readMag(int m[3]);
00132 
00133         /** sets the I2C bus frequency
00134          *
00135          * @param frequency is the I2C bus/clock frequency, either standard (100000) or fast (400000)
00136          */
00137         void frequency(int hz);
00138      
00139     private:
00140         I2C _device;
00141         char _data[6];
00142         int offset[3];
00143         int scale[3];
00144         void init();
00145 };
00146 
00147 #endif