勇帜 周
bird
Diff: Gamepad/Gamepad.cpp
- Revision:
- 0:3887ebee1b37
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/Gamepad/Gamepad.cpp Fri May 03 17:51:38 2019 +0000
@@ -0,0 +1,341 @@
+#include "Gamepad.h"
+
+#include "mbed.h"
+
+//////////// constructor/destructor ////////////
+Gamepad::Gamepad()
+ :
+ _led1(new PwmOut(PTA1)),
+ _led2(new PwmOut(PTA2)),
+ _led3(new PwmOut(PTC2)),
+ _led4(new PwmOut(PTC3)),
+ _led5(new PwmOut(PTC4)),
+ _led6(new PwmOut(PTD3)),
+
+ _button_A(new InterruptIn(PTB9)),
+ _button_B(new InterruptIn(PTD0)),
+ _button_X(new InterruptIn(PTC17)),
+ _button_Y(new InterruptIn(PTC12)),
+ _button_L(new InterruptIn(PTB18)),
+ _button_R(new InterruptIn(PTB3)),
+ _button_back(new InterruptIn(PTB19)),
+ _button_start(new InterruptIn(PTC5)),
+ _button_joystick(new InterruptIn(PTC16)),
+
+ _vert(new AnalogIn(PTB10)),
+ _horiz(new AnalogIn(PTB11)),
+
+ _buzzer(new PwmOut(PTC10)),
+ _pot(new AnalogIn(PTB2)),
+
+ _timeout(new Timeout()),
+
+ _event_state(0),
+
+ _x0(0),
+ _y0(0)
+{}
+
+Gamepad::~Gamepad()
+{
+ delete _led1,_led2,_led3,_led4,_led5,_led6;
+ delete _button_A,_button_B,_button_joystick,_vert,_horiz;
+ delete _button_X,_button_Y,_button_back,_button_start;
+ delete _button_L,_button_R, _buzzer, _pot, _timeout;
+}
+
+///////////////// public methods /////////////////
+
+void Gamepad::init()
+{
+ leds_off();
+ init_buttons();
+
+ // read centred values of joystick
+ _x0 = _horiz->read();
+ _y0 = _vert->read();
+
+ // clear all flags
+ _event_state = 0;
+}
+
+void Gamepad::leds_off()
+{
+ leds(0.0);
+}
+
+void Gamepad::leds_on()
+{
+ leds(1.0);
+}
+
+void Gamepad::leds(float val) const
+{
+ if (val < 0.0f) {
+ val = 0.0f;
+ }
+ if (val > 1.0f) {
+ val = 1.0f;
+ }
+
+ // leds are active-low, so subtract from 1.0
+ // 0.0 corresponds to fully-off, 1.0 to fully-on
+ val = 1.0f - val;
+
+ _led1->write(val);
+ _led2->write(val);
+ _led3->write(val);
+ _led4->write(val);
+ _led5->write(val);
+ _led6->write(val);
+}
+
+void Gamepad::led(int n,float val) const
+{
+ // ensure they are within vlaid range
+ if (val < 0.0f) {
+ val = 0.0f;
+ }
+ if (val > 1.0f) {
+ val = 1.0f;
+ }
+
+ switch (n) {
+
+ // check for valid LED number and set value
+
+ case 1:
+ _led1->write(1.0f-val); // active-low so subtract from 1
+ break;
+ case 2:
+ _led2->write(1.0f-val); // active-low so subtract from 1
+ break;
+ case 3:
+ _led3->write(1.0f-val); // active-low so subtract from 1
+ break;
+ case 4:
+ _led4->write(1.0f-val); // active-low so subtract from 1
+ break;
+ case 5:
+ _led5->write(1.0f-val); // active-low so subtract from 1
+ break;
+ case 6:
+ _led6->write(1.0f-val); // active-low so subtract from 1
+ break;
+
+ }
+}
+
+float Gamepad::read_pot() const
+{
+ return _pot->read();
+}
+
+void Gamepad::tone(float frequency, float duration)
+{
+ _buzzer->period(1.0f/frequency);
+ _buzzer->write(0.5); // 50% duty cycle - square wave
+ _timeout->attach(callback(this, &Gamepad::tone_off), duration );
+}
+
+bool Gamepad::check_event(GamepadEvent const id)
+{
+ // Check whether event flag is set
+ if (_event_state[id]) {
+ _event_state.reset(id); // clear flag
+ return true;
+ } else {
+ return false;
+ }
+}
+
+// this method gets the magnitude of the joystick movement
+float Gamepad::get_mag()
+{
+ Polar p = get_polar();
+ return p.mag;
+}
+
+// this method gets the angle of joystick movement (0 to 360, 0 North)
+float Gamepad::get_angle()
+{
+ Polar p = get_polar();
+ return p.angle;
+}
+
+Direction Gamepad::get_direction()
+{
+ float angle = get_angle(); // 0 to 360, -1 for centred
+
+ Direction d;
+ // partition 360 into segments and check which segment the angle is in
+ if (angle < 0.0f) {
+ d = CENTRE; // check for -1.0 angle
+ } else if (angle < 22.5f) { // then keep going in 45 degree increments
+ d = N;
+ } else if (angle < 67.5f) {
+ d = NE;
+ } else if (angle < 112.5f) {
+ d = E;
+ } else if (angle < 157.5f) {
+ d = SE;
+ } else if (angle < 202.5f) {
+ d = S;
+ } else if (angle < 247.5f) {
+ d = SW;
+ } else if (angle < 292.5f) {
+ d = W;
+ } else if (angle < 337.5f) {
+ d = NW;
+ } else {
+ d = N;
+ }
+
+ return d;
+}
+
+///////////////////// private methods ////////////////////////
+
+void Gamepad::tone_off()
+{
+ // called after timeout
+ _buzzer->write(0.0);
+}
+
+void Gamepad::init_buttons()
+{
+ // turn on pull-downs as other side of button is connected to 3V3
+ // button is 0 when not pressed and 1 when pressed
+ _button_A->mode(PullDown);
+ _button_B->mode(PullDown);
+ _button_X->mode(PullDown);
+ _button_Y->mode(PullDown);
+ _button_back->mode(PullDown);
+ _button_start->mode(PullDown);
+ _button_L->mode(PullDown);
+ _button_R->mode(PullDown);
+ _button_joystick->mode(PullDown);
+ // therefore setup rising edge interrupts
+ _button_A->rise(callback(this,&Gamepad::a_isr));
+ _button_B->rise(callback(this,&Gamepad::b_isr));
+ _button_X->rise(callback(this,&Gamepad::x_isr));
+ _button_Y->rise(callback(this,&Gamepad::y_isr));
+ _button_L->rise(callback(this,&Gamepad::l_isr));
+ _button_R->rise(callback(this,&Gamepad::r_isr));
+ _button_start->rise(callback(this,&Gamepad::start_isr));
+ _button_back->rise(callback(this,&Gamepad::back_isr));
+ _button_joystick->rise(callback(this,&Gamepad::joy_isr));
+}
+
+// button interrupts ISRs
+// Each of these simply sets the appropriate event bit in the _event_state
+// variable
+void Gamepad::a_isr()
+{
+ _event_state.set(A_PRESSED);
+}
+void Gamepad::b_isr()
+{
+ _event_state.set(B_PRESSED);
+}
+void Gamepad::x_isr()
+{
+ _event_state.set(X_PRESSED);
+}
+void Gamepad::y_isr()
+{
+ _event_state.set(Y_PRESSED);
+}
+void Gamepad::l_isr()
+{
+ _event_state.set(L_PRESSED);
+}
+void Gamepad::r_isr()
+{
+ _event_state.set(R_PRESSED);
+}
+void Gamepad::back_isr()
+{
+ _event_state.set(BACK_PRESSED);
+}
+void Gamepad::start_isr()
+{
+ _event_state.set(START_PRESSED);
+}
+void Gamepad::joy_isr()
+{
+ _event_state.set(JOY_PRESSED);
+}
+
+// get raw joystick coordinate in range -1 to 1
+// Direction (x,y)
+// North (0,1)
+// East (1,0)
+// South (0,-1)
+// West (-1,0)
+Vector2D Gamepad::get_coord()
+{
+ // read() returns value in range 0.0 to 1.0 so is scaled and centre value
+ // substracted to get values in the range -1.0 to 1.0
+ float x = 2.0f*( _horiz->read() - _x0 );
+ float y = 2.0f*( _vert->read() - _y0 );
+
+ // Note: the x value here is inverted to ensure the positive x is to the
+ // right. This is simply due to how the potentiometer on the joystick
+ // I was using was connected up. It could have been corrected in hardware
+ // by swapping the power supply pins. Instead it is done in software so may
+ // need to be changed depending on your wiring setup
+
+ Vector2D coord = {-x,y};
+ return coord;
+}
+
+// This maps the raw x,y coord onto a circular grid.
+// See: http://mathproofs.blogspot.co.uk/2005/07/mapping-square-to-circle.html
+Vector2D Gamepad::get_mapped_coord()
+{
+ Vector2D coord = get_coord();
+
+ // do the transformation
+ float x = coord.x*sqrt(1.0f-pow(coord.y,2.0f)/2.0f);
+ float y = coord.y*sqrt(1.0f-pow(coord.x,2.0f)/2.0f);
+
+ Vector2D mapped_coord = {x,y};
+ return mapped_coord;
+}
+
+// this function converts the mapped coordinates into polar form
+Polar Gamepad::get_polar()
+{
+ // get the mapped coordinate
+ Vector2D coord = get_mapped_coord();
+
+ // at this point, 0 degrees (i.e. x-axis) will be defined to the East.
+ // We want 0 degrees to correspond to North and increase clockwise to 359
+ // like a compass heading, so we need to swap the axis and invert y
+ float x = coord.y;
+ float y = coord.x;
+
+ float mag = sqrt(x*x+y*y); // pythagoras
+ float angle = RAD2DEG*atan2(y,x);
+ // angle will be in range -180 to 180, so add 360 to negative angles to
+ // move to 0 to 360 range
+ if (angle < 0.0f) {
+ angle+=360.0f;
+ }
+
+ // the noise on the ADC causes the values of x and y to fluctuate slightly
+ // around the centred values. This causes the random angle values to get
+ // calculated when the joystick is centred and untouched. This is also when
+ // the magnitude is very small, so we can check for a small magnitude and then
+ // set the angle to -1. This will inform us when the angle is invalid and the
+ // joystick is centred
+
+ if (mag < TOL) {
+ mag = 0.0f;
+ angle = -1.0f;
+ }
+
+ Polar p = {mag,angle};
+ return p;
+}
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