LSM303DLHC.h

00001 #ifndef __LSM303DLHC_H
00002 #define __LSM303DLHC_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 REFERENCE_A       0x26
00015 #define STATUS_REG_A      0x27
00016  
00017 #define OUT_X_L_A         0x28
00018 #define OUT_X_H_A         0x29
00019 #define OUT_Y_L_A         0x2A
00020 #define OUT_Y_H_A         0x2B
00021 #define OUT_Z_L_A         0x2C
00022 #define OUT_Z_H_A         0x2D
00023  
00024 #define INT1_CFG_A        0x30
00025 #define INT1_SRC_A        0x31
00026 #define INT1_THS_A        0x32
00027 #define INT1_DURATION_A   0x33
00028 #define INT2_CFG_A        0x34
00029 #define INT2_SRC_A        0x35
00030 #define INT2_THS_A        0x36
00031 #define INT2_DURATION_A   0x37
00032  
00033 #define CRA_REG_M         0x00
00034 #define CRB_REG_M         0x01
00035 #define MR_REG_M          0x02
00036  
00037 #define OUT_X_H_M         0x03
00038 #define OUT_X_L_M         0x04
00039 #define OUT_Y_H_M         0x07
00040 #define OUT_Y_L_M         0x08
00041 #define OUT_Z_H_M         0x05
00042 #define OUT_Z_L_M         0x06
00043  
00044 #define SR_REG_M          0x09
00045 #define IRA_REG_M         0x0A
00046 #define IRB_REG_M         0x0B
00047 #define IRC_REG_M         0x0C
00048    
00049 /** Tilt-compensated compass interface Library for the STMicro LSM303DLm 3-axis magnetometer, 3-axis acceleromter
00050  * @author Michael Shimniok http://www.bot-thoughts.com/
00051  *
00052  * This is an early revision; I've not yet implemented heading calculation and the interface differs from my
00053  * earlier LSM303DLH; I hope to make this library drop in compatible at some point in the future.
00054  * setScale() and setOffset() have no effect at this time.
00055  *
00056  * @code
00057  * #include "mbed.h"
00058  * #include "LSM303DLM.h"
00059  *
00060  * LSM303DLM compass(p28, p27);
00061  * ...
00062  * int a[3], m[3];
00063  * ...
00064  * compass.readAcc(a);
00065  * compass.readMag(m);
00066  *
00067  * @endcode
00068  */
00069 class LSM303DLHC {
00070  
00071     public:
00072         /** Create a new interface for an LSM303DLM
00073          *
00074          * @param sda is the pin for the I2C SDA line
00075          * @param scl is the pin for the I2C SCL line
00076          */
00077         LSM303DLHC(PinName sda, PinName scl);
00078  
00079         /** sets the x, y, and z offset corrections for hard iron calibration
00080          * 
00081          * Calibration details here:
00082          *  http://mbed.org/users/shimniok/notebook/quick-and-dirty-3d-compass-calibration/
00083          *
00084          * If you gather raw magnetometer data and find, for example, x is offset
00085          * by hard iron by -20 then pass +20 to this member function to correct
00086          * for hard iron.
00087          *
00088          * @param x is the offset correction for the x axis
00089          * @param y is the offset correction for the y axis
00090          * @param z is the offset correction for the z axis
00091          */
00092         void init();
00093         void setOffset(float x, float y, float z);
00094         
00095         /** sets the scale factor for the x, y, and z axes
00096          *
00097          * Calibratio details here:
00098          *  http://mbed.org/users/shimniok/notebook/quick-and-dirty-3d-compass-calibration/
00099          *
00100          * Sensitivity of the three axes is never perfectly identical and this
00101          * function can help to correct differences in sensitivity.  You're
00102          * supplying a multipler such that x, y and z will be normalized to the
00103          * same max/min values
00104          */
00105         void setScale(float x, float y, float z);
00106  
00107         /** read the calibrated accelerometer and magnetometer values
00108          *
00109          * @param a is the accelerometer 3d vector, written by the function
00110          * @param m is the magnetometer 3d vector, written by the function
00111          */
00112         void read(int a[3], int m[3]);
00113         
00114         /** read the calibrated accelerometer values
00115          *
00116          * @param a is the accelerometer 3d vector, written by the function
00117          */
00118         void readAcc(int a[3]);
00119  
00120         /** read the calibrated magnetometer values
00121          *
00122          * @param m is the magnetometer 3d vector, written by the function
00123          */
00124         void readMag(int m[3]);
00125  
00126         /** sets the I2C bus frequency
00127          *
00128          * @param frequency is the I2C bus/clock frequency, either standard (100000) or fast (400000)
00129          */
00130         void frequency(int hz);
00131      
00132     private:
00133         I2C _device;
00134         char _data[6];
00135         int offset[3];
00136         int scale[3];
00137 };
00138  
00139 #endif