Joystick.h

00001 #ifndef JOYSTICK_H
00002 #define JOYSTICK_H
00003 
00004 #include "mbed.h"
00005 
00006 // this value can be tuned to alter tolerance of joystick movement
00007 #define TOL 0.1f
00008 #define RAD2DEG 57.2957795131f
00009 
00010 enum Direction {
00011     CENTRE,  // 0
00012     N,       // 1
00013     NE,      // 2
00014     E,       // 3
00015     SE,      // 4
00016     S,       // 5
00017     SW,      // 6
00018     W,       // 7
00019     NW      // 8
00020 };
00021 
00022 struct Vector2D {
00023   float x;
00024   float y;  
00025 };
00026 
00027 struct Polar {
00028     float mag;
00029     float angle;
00030 };
00031 
00032 /** Joystick Class
00033 @author Dr Craig A. Evans, University of Leeds
00034 @brief  Library for interfacing with analogue joystick
00035 
00036 Example:
00037 
00038 @code
00039 
00040 #include "mbed.h"
00041 #include "Joystick.h"
00042 
00043 //                  y     x     button
00044 Joystick joystick(PTB11,PTB10);
00045 
00046 int main() {
00047     
00048     joystick.init();
00049     
00050     while(1) {
00051     
00052         Vector2D coord = joystick.get_coord();
00053         printf("Coord = %f,%f\n",coord.x,coord.y);
00054         
00055         Vector2D mapped_coord = joystick.get_mapped_coord(); 
00056         printf("Mapped coord = %f,%f\n",mapped_coord.x,mapped_coord.y); 
00057         
00058         float mag = joystick.get_mag();
00059         float angle = joystick.get_angle();
00060         printf("Mag = %f Angle = %f\n",mag,angle);
00061         
00062         Direction d = joystick.get_direction();
00063         printf("Direction = %i\n",d);
00064     
00065           
00066         wait(0.5);
00067     }
00068     
00069     
00070 }
00071 
00072 * @endcode
00073 */
00074 class Joystick
00075 {
00076 public:
00077     
00078     //              y-pot              x-pot            
00079     Joystick(PinName vertPin,PinName horizPin);
00080     
00081     void init();  // needs to be called at start with joystick centred
00082     float get_mag();              // polar
00083     float get_angle();            // polar
00084     Vector2D get_coord();         // cartesian co-ordinates x,y
00085     Vector2D get_mapped_coord();  // x,y mapped to circle
00086     Direction get_direction();    // N,NE,E,SE etc.
00087     Polar get_polar();            // mag and angle in struct form
00088     
00089 private:
00090 
00091     AnalogIn *vert;
00092     AnalogIn *horiz;
00093        
00094     // centred x,y values    
00095     float _x0;
00096     float _y0;
00097     
00098 };
00099 
00100 #endif