Diff: Accelerometer.cpp

Revision:

7:1e00dfecc92d

Parent:

6:3facf0329142

Child:

8:862e28c7f6f6

--- a/Accelerometer.cpp	Sun Jan 15 02:04:23 2017 +0000
+++ b/Accelerometer.cpp	Sun Jan 15 02:08:32 2017 +0000
@@ -1,147 +1,150 @@
 #include "Accelerometer.hpp"
 #include "Utility.hpp"
 
-//Compute inverse two's complement to obtain a signed value
-//See page 21: https://www.gel.usherbrooke.ca/s5info/h17/doc/app1/file/MMA8452Q.pdf
-//See: https://en.wikipedia.org/wiki/Two's_complement
-//Turns out, the signed char does it for free
-//We have to specify "signed char" because the "standard does not specify if plain char is signed or unsigned"
-//http://stackoverflow.com/a/2054941/3212785
-int raw_axis_data_to_int(signed char raw_axis_data)
-{
-    return raw_axis_data;
-}
-
-char get_axis_register(Axis axis)
-{
-    switch(axis)
-    {
-        case AXIS_X: return OUT_X_MSB_REGISTER;
-        case AXIS_Y: return OUT_Y_MSB_REGISTER;
-        case AXIS_Z: return OUT_Z_MSB_REGISTER;
-        default: return AXIS_INVALID;
-    }
-}
-    
-double g_force_from_int_axis_data(const int axis_data)
-{
-    return (double)axis_data / 64.0;
-}
-
-//Z axis is perpendicular to the horizontal plane, towards the floor when the accelerometer is flat
-//Therefore, 
-// - if the Z force is +1g, the accelerometer is flat
-// - if the Z force is -1g, the accelerometer is upside down
-// - if the Z force is 0g, the accelerometer 90 degree from the horizontal
-//sin(theta) = Z force in g
-double angle_from_int_axis_data(const int axis_data)
+namespace accelerometer
 {
-    const double z_g_force = g_force_from_int_axis_data(axis_data);
-    const double angle_radian = acos(fabs(z_g_force));
-    return utility::degree_from_radian(angle_radian);
-}
-
-Accelerometer::Accelerometer(
-    PinName sda_pin, 
-    PinName scl_pin, 
-    const int slave_address
-    ) :
-    device(sda_pin, scl_pin),
-    slave_address(slave_address)
-{
-}
-
-void Accelerometer::write_register(const char register_address, const char new_value)
-{
-    const int left_shifted_slave_address = slave_address << 1;
-    char data[2];
-    data[0] = register_address;
-    data[1] = new_value;
-
-    const int write_return = device.write(left_shifted_slave_address, data, 2);
-    if(write_return < 0)
+    //Compute inverse two's complement to obtain a signed value
+    //See page 21: https://www.gel.usherbrooke.ca/s5info/h17/doc/app1/file/MMA8452Q.pdf
+    //See: https://en.wikipedia.org/wiki/Two's_complement
+    //Turns out, the signed char does it for free
+    //We have to specify "signed char" because the "standard does not specify if plain char is signed or unsigned"
+    //http://stackoverflow.com/a/2054941/3212785
+    int raw_axis_data_to_int(signed char raw_axis_data)
+    {
+        return raw_axis_data;
+    }
+    
+    char get_axis_register(Axis axis)
+    {
+        switch(axis)
+        {
+            case AXIS_X: return OUT_X_MSB_REGISTER;
+            case AXIS_Y: return OUT_Y_MSB_REGISTER;
+            case AXIS_Z: return OUT_Z_MSB_REGISTER;
+            default: return AXIS_INVALID;
+        }
+    }
+        
+    double g_force_from_int_axis_data(const int axis_data)
     {
-        printf("Write error: I2C error");
+        return (double)axis_data / 64.0;
+    }
+    
+    //Z axis is perpendicular to the horizontal plane, towards the floor when the accelerometer is flat
+    //Therefore, 
+    // - if the Z force is +1g, the accelerometer is flat
+    // - if the Z force is -1g, the accelerometer is upside down
+    // - if the Z force is 0g, the accelerometer 90 degree from the horizontal
+    //sin(theta) = Z force in g
+    double angle_from_int_axis_data(const int axis_data)
+    {
+        const double z_g_force = g_force_from_int_axis_data(axis_data);
+        const double angle_radian = acos(fabs(z_g_force));
+        return utility::degree_from_radian(angle_radian);
     }
-}
-
-char Accelerometer::read_register(const char register_address)
-{
-    char result;
-    const int left_shifted_slave_address = slave_address << 1;
-
-    const int write_return = device.write(left_shifted_slave_address, &register_address, 1, true);
-    if(write_return < 0)
+    
+    Accelerometer::Accelerometer(
+        PinName sda_pin, 
+        PinName scl_pin, 
+        const int slave_address
+        ) :
+        device(sda_pin, scl_pin),
+        slave_address(slave_address)
+    {
+    }
+    
+    void Accelerometer::write_register(const char register_address, const char new_value)
+    {
+        const int left_shifted_slave_address = slave_address << 1;
+        char data[2];
+        data[0] = register_address;
+        data[1] = new_value;
+    
+        const int write_return = device.write(left_shifted_slave_address, data, 2);
+        if(write_return < 0)
+        {
+            printf("Write error: I2C error");
+        }
+    }
+    
+    char Accelerometer::read_register(const char register_address)
     {
-        printf("Write error: I2C error");
-    }
-
-    const int read_return = device.read(left_shifted_slave_address, &result, 1);
-    if(read_return != 0)
-    {
-        printf("Read error: I2C error (nack)");
+        char result;
+        const int left_shifted_slave_address = slave_address << 1;
+    
+        const int write_return = device.write(left_shifted_slave_address, &register_address, 1, true);
+        if(write_return < 0)
+        {
+            printf("Write error: I2C error");
+        }
+    
+        const int read_return = device.read(left_shifted_slave_address, &result, 1);
+        if(read_return != 0)
+        {
+            printf("Read error: I2C error (nack)");
+        }
+    
+        return result;
     }
-
-    return result;
-}
-
-//axis_data must be an array of 6 bytes
-void Accelerometer::read_all_axis(signed char* axis_data)
-{
-    for(int i = 0; i < NUMBER_OF_DATA_REGISTERS; ++i)
+    
+    //axis_data must be an array of 6 bytes
+    void Accelerometer::read_all_axis(signed char* axis_data)
     {
-        const char current_register = OUT_X_MSB_REGISTER + i;
-        axis_data[i] = read_register(current_register);
+        for(int i = 0; i < NUMBER_OF_DATA_REGISTERS; ++i)
+        {
+            const char current_register = OUT_X_MSB_REGISTER + i;
+            axis_data[i] = read_register(current_register);
+        }
     }
-}
-
-void Accelerometer::print_all_axis_data()
-{
-    signed char axis_data[NUMBER_OF_DATA_REGISTERS];
-    for(int i=0; i<NUMBER_OF_DATA_REGISTERS; i++)
-    {
-        axis_data[i] = 0;
-    }
-
-    read_all_axis(axis_data);
-
-    printf("Register content: ");
-    for(int i=0; i<NUMBER_OF_DATA_REGISTERS; i++)
+    
+    void Accelerometer::print_all_axis_data()
     {
-        const int current_data = (int)(axis_data[i]);
-        printf("%d, ", current_data);
+        signed char axis_data[NUMBER_OF_DATA_REGISTERS];
+        for(int i=0; i<NUMBER_OF_DATA_REGISTERS; i++)
+        {
+            axis_data[i] = 0;
+        }
+    
+        read_all_axis(axis_data);
+    
+        printf("Register content: ");
+        for(int i=0; i<NUMBER_OF_DATA_REGISTERS; i++)
+        {
+            const int current_data = (int)(axis_data[i]);
+            printf("%d, ", current_data);
+        }
+        printf("\r\n");
+    }
+    
+    void Accelerometer::set_standby()
+    {
+        const char previous_ctrl_reg1 = read_register(CTRL_REG1_REGISTER_ADDRESS);
+        const char new_ctrl_reg1_value = previous_ctrl_reg1 & ~(0x01);
+        write_register(CTRL_REG1_REGISTER_ADDRESS, new_ctrl_reg1_value);
     }
-    printf("\r\n");
-}
-
-void Accelerometer::set_standby()
-{
-    const char previous_ctrl_reg1 = read_register(CTRL_REG1_REGISTER_ADDRESS);
-    const char new_ctrl_reg1_value = previous_ctrl_reg1 & ~(0x01);
-    write_register(CTRL_REG1_REGISTER_ADDRESS, new_ctrl_reg1_value);
-}
-
-void Accelerometer::set_active()
-{
-    const char previous_ctrl_reg1 = read_register(CTRL_REG1_REGISTER_ADDRESS);
-    const char new_ctrl_reg1_value = previous_ctrl_reg1 | 0x01;
-    write_register(CTRL_REG1_REGISTER_ADDRESS, new_ctrl_reg1_value);
-}
-
-void Accelerometer::init()
-{
-    set_active();
-}
-
-int Accelerometer::read_axis_data_8_bits(Axis axis)
-{
-    const char axis_register = get_axis_register(axis);
-    const char register_value = read_register(axis_register);
-    return raw_axis_data_to_int(register_value);
-}
-
-double Accelerometer::get_angle_from_horizontal()
-{
-    const int z_axis_data = read_axis_data_8_bits(AXIS_Z);
-    return angle_from_int_axis_data(z_axis_data);
-}
\ No newline at end of file
+    
+    void Accelerometer::set_active()
+    {
+        const char previous_ctrl_reg1 = read_register(CTRL_REG1_REGISTER_ADDRESS);
+        const char new_ctrl_reg1_value = previous_ctrl_reg1 | 0x01;
+        write_register(CTRL_REG1_REGISTER_ADDRESS, new_ctrl_reg1_value);
+    }
+    
+    void Accelerometer::init()
+    {
+        set_active();
+    }
+    
+    int Accelerometer::read_axis_data_8_bits(Axis axis)
+    {
+        const char axis_register = get_axis_register(axis);
+        const char register_value = read_register(axis_register);
+        return raw_axis_data_to_int(register_value);
+    }
+    
+    double Accelerometer::get_angle_from_horizontal()
+    {
+        const int z_axis_data = read_axis_data_8_bits(AXIS_Z);
+        return angle_from_int_axis_data(z_axis_data);
+    }
+};
\ No newline at end of file