MD25.h

00001 // ***********************************************************************
00002 // MBED MD25 H-bridge Motor Controller.
00003 //
00004 // Based on Arduino code by Richie Reynolds
00005 // ***********************************************************************
00006 #ifndef MBED_MD25_h
00007 #define MBED_MD25_h
00008 
00009 #include "mbed.h"
00010 
00011 #define     MD25_DEFAULT_ADDRESS    0xB0
00012 //
00013 // modes
00014 //
00015 //  Mode        Description
00016 //   0    Skid-steer with unsigned speed values (STOP = 128)
00017 //   1    Skid-steer with signed speed values  (STOP = 0)
00018 //   2    Forward/turn steer with unsigned values (speed1 to control both motors, speed2 for turn)
00019 //   3    Forward/turn steer with signed values (speed1 to control both motors, speed2 for turn)
00020 //
00021 #define     MODE_0       0
00022 #define     MODE_1       1
00023 #define     MODE_2       2
00024 #define     MODE_3       3
00025 
00026 //
00027 // register definitions
00028 //
00029 #define     MD25_SPEED1_REG         0
00030 #define     MD25_SPEED2_REG         1
00031 #define     MD25_ENCODER1_REG       2
00032 #define     MD25_ENCODER2_REG       6
00033 #define     MD25_VOLTAGE_REG        10
00034 #define     MD25_CURRENT1_REG       11
00035 #define     MD25_CURRENT2_REG       12
00036 #define     MD25_SOFTWAREVER_REG    13
00037 #define     MD25_ACCELRATE_REG      14
00038 #define     MD25_MODE_REG           15
00039 #define     MD25_CMD_REG            16        // command register
00040 //
00041 // Command register command set
00042 //
00043 #define     MD25_RESET_ENCODERS             0x20
00044 #define     MD25_DIABLE SPEED_REGULATION    0x30
00045 #define     MD25_ENABLE_SPEED_REGULATION    0x31
00046 #define     MD25_DISABLE_TIMEOUT            0x32
00047 #define     MD25_ENABLE_TIMEOUT             0x33
00048 
00049 /** MD25 class
00050  *
00051  * Allow access to an MD25 Dual 12V 2.8A H-Bridge DC Motor Driver
00052  *
00053  * @code
00054  *      MD25  motor_control(p9,p10);   // assumes default address of 0xB0
00055  * or
00056  *      MD25  motor_control(p9, p10, 0xB0);
00057  * @endcode
00058  */
00059 class MD25 {
00060 public:
00061     /** Constructor for the MD25 connected to specified I2C pins at a specified address
00062      *
00063      * @param   sda         I2C data pin
00064      * @param   scl         I2C clock pin
00065      * @param   i2cAddress  I2C address
00066      */
00067     MD25(PinName sda, PinName scl, int MD25_i2cAddress);
00068 
00069     /** Constructor for the MD25 connected to specified I2C pins at default address
00070      *
00071      * @param   sda         I2C data pin
00072      * @param   scl         I2C clock pin
00073      */
00074     MD25(PinName sda, PinName scl);
00075 
00076     /** Read encoder for channel 1
00077      *
00078      * @return   32-bit signed integer value of current encoder value for channel 1
00079      */
00080     int32_t getEncoder1(void);
00081     
00082     /** Read encoder for channel 2
00083      *
00084      * @return   32-bit signed integer value of current encoder value for channel 2
00085      */
00086     int32_t getEncoder2(void);
00087 
00088     /** set speed registers for both channels
00089      *
00090      * Effect of value is dependent on system mode
00091      *
00092      * @param   speed_1   speed register for channel 1  (0->255)
00093      * @param   speed_2   speed register for channel 2  (0->255)
00094      */    
00095     void setSpeedRegisters(uint8_t speed_1, uint8_t speed_2);    
00096     
00097     /** set speed register for  channel 1
00098      *
00099      * Effect of value is dependent on system mode
00100      *
00101      * @param   speed_1   speed register for channel 1  (0->255)
00102      */        
00103     void setSpeed1Reg(uint8_t speed);
00104     
00105     /** set speed register for  channel 2
00106      *
00107      * Effect of value is dependent on system mode
00108      *
00109      * @param   speed_2   speed register for channel 2  (0->255)
00110      */        
00111     void setSpeed2Reg(uint8_t speed);
00112     
00113     /** switch motor 1 off
00114      */        
00115     void stopMotor1(void);
00116     
00117     /** switch motor 2 off
00118      */        
00119     void stopMotor2(void);
00120           
00121     /** switch both motors off
00122      */
00123     void stopMotors(void);
00124     
00125     /** read current software version
00126      *
00127      * @return   version number
00128      */    
00129     uint32_t getSoftwareVersion(void);
00130     
00131     /** read battery voltage
00132      *
00133      * @return   voltage value in float format
00134      */        
00135     float getBatteryVolts(void);
00136     
00137     /** read acceleration rate
00138      *
00139      * @return   acceleration rate
00140      */
00141     uint8_t getAccelerationRate(void);
00142 
00143     /** read current from motor channel 1
00144      *
00145      * @return   current value
00146      */    
00147     uint8_t getMotor1Current(void);
00148     
00149     /** read current from motor channel 2
00150      *
00151      * @return   current value in apprx. units of 0.1amp
00152      */        
00153     uint8_t getMotor2Current(void);
00154     
00155     /** read current speed register for motor channel 1
00156      *
00157      * @return   speed value (0->255); meaning dependent on mode
00158      */       
00159     uint8_t getMotor1Speed(void);
00160     
00161     /** read current speed register for motor channel 2
00162      *
00163      * @return   speed value (0->255); meaning dependent on mode
00164      */           
00165     uint8_t getMotor2Speed(void);
00166     
00167     /** read current mode
00168      *
00169      * @return   mode value (0, 1, 2, or 3); default is mode 0
00170      */
00171     uint8_t getMode(void);
00172     
00173     /** set system mode
00174      *
00175      * @param   mode     value (0, 1, 2, or 3)
00176      */    
00177     void setMode(uint8_t mode);
00178     
00179     /** set acceleration rate
00180      *
00181      * @param   rate   acceleration rate
00182      */      
00183     void setAccelerationRate(uint8_t rate);
00184     
00185     /** send command to command register
00186      *
00187      * @param   command   command code
00188      *
00189      * MD25_RESET_ENCODERS             0x20
00190      * MD25_DIABLE SPEED_REGULATION    0x30
00191      * MD25_ENABLE_SPEED_REGULATION    0x31
00192      * MD25_DISABLE_TIMEOUT            0x32
00193      * MD25_ENABLE_TIMEOUT             0x33
00194      */      
00195     void setCommand(uint8_t command);
00196 
00197 private:
00198     I2C       _i2c;
00199     uint8_t   current_mode;
00200     uint8_t   MD25_i2cAddress;
00201 
00202     uint8_t   readRegisterbyte(uint8_t reg);
00203     void      writeRegisterbyte(uint8_t reg, uint8_t value);
00204 };
00205 
00206 #endif // MBED_md25_h