Joystick.cpp

00001 #include "Joystick.h"
00002 #include "mbed.h"
00003 #include <cmath>
00004 
00005 /// @file Joystick.cpp
00006 
00007 Joystick::Joystick(PinName x, PinName y, PinName button)
00008 {
00009     xPot = new AnalogIn(x);
00010     yPot = new AnalogIn(y);
00011     btn = new DigitalIn(button);
00012 }
00013 
00014 Joystick::~Joystick()
00015 {
00016     delete xPot;
00017     delete yPot;
00018     delete btn;
00019 }
00020 
00021 
00022 // Make sure that the Joystick is centered while calibrating
00023 void Joystick::calibrate()
00024 {
00025     btn->mode(PullDown);
00026     centerX = *xPot;
00027     centerY = *yPot;
00028 }
00029 
00030 
00031 void Joystick::update()
00032 {
00033     // Get position of joystick compared to the center values (delta x and delta y).
00034     dx = *xPot - centerX;
00035     dy = *yPot - centerY;
00036     
00037     if (abs(dx) < DEAD_ZONE && abs(dy) < DEAD_ZONE)
00038         dir = CENTER;
00039     else if (abs(dx) < DEAD_ZONE)                       // Inside horizontal dead zone.
00040         dir = (dy > DEAD_ZONE) ? UP : DOWN;
00041     else if (abs(dy) < DEAD_ZONE)                       // Inside vertical dead zone.
00042         dir = (dx > DEAD_ZONE) ? LEFT : RIGHT;
00043     else if (dx > 0)                                    // To the left, outside both deadzones.
00044         dir = (dy > 0) ? UP_LEFT : DOWN_LEFT; 
00045     else                                                // To the right, outside both deadzones
00046         dir = (dy > 0) ? UP_RIGHT : DOWN_RIGHT;
00047 }