PositionSystem.h

00001 #include "USBHostMouse.h"
00002 #include "HMC6352.h"
00003 
00004 #define PFLAG_ON 0
00005 #define PFLAG_OFF 1
00006 #define PFLAG_CALIB 2
00007 #define PTURN_SPEED (0.5)
00008 
00009 float PTURN_RIGHT = 0;
00010 
00011 extern Serial pc(USBTX, USBRX);
00012 
00013 // updates xy position if on, does nothing if off
00014 extern char PFlag = PFLAG_ON;
00015 
00016 // whenever a turn is complete, this should store 
00017 // the degrees facing (0, 90, 180, 270) in system
00018 extern int t_position = 0;
00019 
00020 // variables to keep track of coordinate position
00021 float x_position = 0;
00022 float y_position = 0;
00023 
00024 // variables to keep track of movement during turning
00025 float pturn_x = 0;
00026 float pturn_y = 0;
00027 
00028 /* mouse event handler */
00029 void onMouseEvent(uint8_t buttons, int8_t x_mickey, int8_t y_mickey, int8_t z) {
00030     
00031     // calculate new position 
00032     if(PFlag == PFLAG_ON) {
00033         
00034         // mouse movements are in mickeys. 1 mickey = ~230 DPI = ~1/230th of an inch
00035         float temp = y_mickey / 232.6;
00036         
00037         // determine direction we are facing and add to that direction
00038         if(t_position == 0)
00039             y_position += temp;
00040         else if(t_position == 90)
00041             x_position += temp;
00042         else if(t_position == 180)
00043             y_position -= temp;
00044         else
00045             x_position -= temp;
00046     } else if(PFlag == PFLAG_CALIB) {    
00047         PTURN_RIGHT += x_mickey / 232.6;
00048     } else {
00049         pturn_x += x_mickey / 232.6;
00050         pturn_y += y_mickey / 232.6;
00051     }
00052 }
00053 
00054 // intialize x and y variables for turning
00055 void turnInit() {
00056     pturn_x = 0;
00057     pturn_y = 0;
00058 }
00059     
00060 /* positioning system thread function */
00061 void PositionSystemMain(void const *) {
00062     
00063     USBHostMouse mouse;
00064     
00065     while(1) {
00066         // try to connect a USB mouse
00067         while(!mouse.connect())
00068             Thread::wait(500);
00069     
00070         // when connected, attach handler called on mouse event
00071         mouse.attachEvent(onMouseEvent);
00072         
00073         // wait until the mouse is disconnected
00074         while(mouse.connected())
00075             Thread::wait(500);
00076     }
00077 }