MAG3110.h

00001 /*
00002  * MAG3110 Sensor Library for mbed
00003  * TODO: Add proper header
00004  */
00005 
00006 #ifndef MAG3110_H
00007 #define MAG3110_H
00008 
00009 #include "mbed.h"
00010 #include "MotionSensor.h"
00011 
00012 #define PI 3.14159265359
00013 
00014 #define MAG_ADDR 0x1D
00015 
00016 // define registers
00017 #define MAG_DR_STATUS 0x00
00018 #define MAG_OUT_X_MSB 0x01
00019 #define MAG_OUT_X_LSB 0x02
00020 #define MAG_OUT_Y_MSB 0x03
00021 #define MAG_OUT_Y_LSB 0x04
00022 #define MAG_OUT_Z_MSB 0x05
00023 #define MAG_OUT_Z_LSB 0x06
00024 #define MAG_WHOAMI  0x07
00025 #define MAG_SYSMOD    0x08
00026 #define MAG_OFF_X_MSB 0x09
00027 #define MAG_OFF_X_LSB 0x0A
00028 #define MAG_OFF_Y_MSB 0x0B
00029 #define MAG_OFF_Y_LSB 0x0C
00030 #define MAG_OFF_Z_MSB 0x0D
00031 #define MAG_OFF_Z_LSB 0x0E
00032 #define MAG_DIE_TEMP  0x0F
00033 #define MAG_CTRL_REG1 0x10
00034 #define MAG_CTRL_REG2 0x11
00035 
00036 // what should WHO_AM_I return?
00037 #define MAG_3110_WHO_AM_I_VALUE 0xC4
00038 
00039 
00040 // Fields in registers
00041 // CTRL_REG1: dr2,dr1,dr0  os1,os0  fr tm ac
00042 
00043 // Sampling rate from 80Hz down to 0.625Hz
00044 #define MAG_3110_SAMPLE80 0
00045 #define MAG_3110_SAMPLE40 0x20
00046 #define MAG_3110_SAMPLE20 0x40
00047 #define MAG_3110_SAMPLE10 0x60
00048 #define MAG_3110_SAMPLE5 0x80
00049 #define MAG_3110_SAMPLE2_5 0xA0
00050 #define MAG_3110_SAMPLE1_25 0xC0
00051 #define MAG_3110_SAMPLE0_625 0xE0
00052 
00053 // How many samples to average (lowers data rate)
00054 #define MAG_3110_OVERSAMPLE1 0
00055 #define MAG_3110_OVERSAMPLE2 0x08
00056 #define MAG_3110_OVERSAMPLE3 0x10
00057 #define MAG_3110_OVERSAMPLE4 0x18
00058 
00059 // read only 1 byte per axis
00060 #define MAG_3110_FASTREAD 0x04
00061 // do one measurement (even if in standby mode)
00062 #define MAG_3110_TRIGGER 0x02
00063 // put in active mode
00064 #define MAG_3110_ACTIVE 0x01
00065 
00066 // CTRL_REG2: AUTO_MRST_EN  _ RAW MAG_RST _ _ _ _ _
00067 // reset sensor after each reading
00068 #define MAG_3110_AUTO_MRST_EN 0x80
00069 // don't subtract user offsets
00070 #define MAG_3110_RAW 0x20
00071 // reset magnetic sensor after too-large field
00072 #define MAG_3110_MAG_RST 0x10
00073 
00074 // DR_STATUS Register ZYXOW ZOW YOW XOW ZYXDR ZDR YDR XDR
00075 #define MAG_3110_ZYXDR  0x08
00076 
00077 /**
00078  * MAG3110 Class to read X/Y/Z data from the magentometer
00079  *
00080  */
00081 class MAG3110 : public MotionSensor
00082 {
00083 public:
00084     /**
00085      * Main constructor
00086      * @param sda SDA pin
00087      * @param sdl SCL pin
00088      * @param addr addr of the I2C peripheral
00089      */
00090     MAG3110(PinName sda, PinName scl);
00091 
00092     void enable(void);
00093     void disable(void);
00094     uint32_t sampleRate(uint32_t fequency);
00095     uint32_t whoAmI(void);
00096     uint32_t dataReady(void);
00097     void getX(int16_t * x);
00098     void getY(int16_t * y);
00099     void getZ(int16_t * z);
00100     void getX(float * x);
00101     void getY(float * y);
00102     void getZ(float * z);
00103     void getAxis(MotionSensorDataCounts &data);
00104     void getAxis(MotionSensorDataUnits &data);
00105     void readRegs(int addr, uint8_t * data, int len);
00106   
00107 private:
00108   I2C m_i2c;
00109   char m_addr;
00110   int16_t getMagAxis(uint8_t addr);
00111   void writeRegs(uint8_t * data, int len);
00112 
00113 };
00114 #endif