Diff: Gamepad2/Gamepad.cpp

Revision:

1:a3f43007030e

diff -r b7f1f47bb26a -r a3f43007030e Gamepad2/Gamepad.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Gamepad2/Gamepad.cpp	Tue Mar 24 18:02:01 2020 +0000
@@ -0,0 +1,464 @@
+#include "Gamepad.h"
+
+#include "mbed.h"
+
+//////////// constructor/destructor ////////////
+Gamepad::Gamepad()
+    :
+    _led1(new PwmOut(PTA2)),
+    _led2(new PwmOut(PTC2)),
+    _led3(new PwmOut(PTC3)),
+    _led4(new PwmOut(PTA1)),
+    _led5(new PwmOut(PTC10)),
+    _led6(new PwmOut(PTC11)),
+
+    _button_A(new InterruptIn(PTC7)),
+    _button_B(new InterruptIn(PTC9)),
+    _button_X(new InterruptIn(PTC5)),
+    _button_Y(new InterruptIn(PTC0)),
+    _button_start(new InterruptIn(PTC8)),
+
+    _vert(new AnalogIn(PTB11)),
+    _horiz(new AnalogIn(PTB10)),
+
+    _pot1(new AnalogIn(PTB2)),
+    _pot2(new AnalogIn(PTB3)),
+
+    dac(new AnalogOut(DAC0_OUT)),
+    ticker(new Ticker),
+    timeout(new Timeout),
+    note_timeout(new Timeout),
+
+    _x0(0),
+    _y0(0)
+{}
+
+
+///////////////// public methods /////////////////
+
+void Gamepad::init()
+{
+    leds_off();
+
+    // read centred values of joystick
+    _x0 = _horiz->read();
+    _y0 = _vert->read();
+
+    // Set all buttons to PullUp
+    _button_A->mode(PullUp);
+    _button_B->mode(PullUp);
+    _button_X->mode(PullUp);
+    _button_Y->mode(PullUp);
+    _button_start->mode(PullUp);
+
+    // Set up interrupts for the fall of buttons
+    _button_A->fall(callback(this,&Gamepad::A_fall_interrupt));
+    _button_B->fall(callback(this,&Gamepad::B_fall_interrupt));
+    _button_X->fall(callback(this,&Gamepad::X_fall_interrupt));
+    _button_Y->fall(callback(this,&Gamepad::Y_fall_interrupt));
+    _button_start->fall(callback(this,&Gamepad::start_fall_interrupt));
+
+    // initalise button flags
+    reset_buttons();
+
+    // number of samples
+    _n = 16;
+    _sample_array = new float[_n];
+
+    // create sample array for one period between 0.0 and 1.0
+    for (int i = 0; i < _n ; i++) {
+        _sample_array[i] = 0.5f + 0.5f*sin(i*2*PI/_n);
+        //printf("y[%i] = %f\n",i,_sample_array[i]);
+    }
+
+}
+
+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 valid 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_pot1() const
+{
+    return _pot1->read();
+}
+
+float Gamepad::read_pot2() const
+{
+    return _pot2->read();
+}
+
+
+// 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;
+}
+
+void Gamepad::reset_buttons()
+{
+    A_fall = B_fall = X_fall = Y_fall = start_fall = false;
+}
+
+bool Gamepad::A_pressed()
+{
+    if (A_fall) {
+        A_fall = false;
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool Gamepad::B_pressed()
+{
+    if (B_fall) {
+        B_fall = false;
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool Gamepad::X_pressed()
+{
+    if (X_fall) {
+        X_fall = false;
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool Gamepad::Y_pressed()
+{
+    if (Y_fall) {
+        Y_fall = false;
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool Gamepad::start_pressed()
+{
+    if (start_fall) {
+        start_fall = false;
+        return true;
+    } else {
+        return false;
+    }
+}
+
+bool Gamepad::A_held()
+{
+    // Buttons are configured as PullUp hence the not
+    return !_button_A->read();
+}
+
+bool Gamepad::B_held()
+{
+    return !_button_B->read();
+}
+
+bool Gamepad::X_held()
+{
+    return !_button_X->read();
+}
+
+bool Gamepad::Y_held()
+{
+    return !_button_Y->read();
+}
+
+bool Gamepad::start_held()
+{
+    return !_button_start->read();
+}
+
+///////////////////// private methods ////////////////////////
+
+// 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 y value here is inverted to ensure the positive y is up
+
+    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;
+}
+
+// ISRs for buttons
+void Gamepad::A_fall_interrupt()
+{
+    A_fall = true;
+}
+void Gamepad::B_fall_interrupt()
+{
+    B_fall = true;
+}
+void Gamepad::X_fall_interrupt()
+{
+    X_fall = true;
+}
+void Gamepad::Y_fall_interrupt()
+{
+    Y_fall = true;
+}
+void Gamepad::start_fall_interrupt()
+{
+    start_fall = true;
+}
+
+void Gamepad::set_bpm(float bpm)
+{
+    _bpm = bpm;
+}
+
+void Gamepad::tone(float frequency,float duration)
+{
+    // calculate time step between samples
+    float dt = 1.0f/(frequency*_n);
+    // start from beginning of LUT
+    _sample = 0;
+
+    // setup ticker and timeout to stop ticker
+
+    // the ticker repeats every dt to plat each sample in turn
+    ticker->attach(callback(this, &Gamepad::ticker_isr), dt);
+    // the timeout stops the ticker after the required duration
+    timeout->attach(callback(this, &Gamepad::timeout_isr), duration );
+}
+
+void Gamepad::play_melody(int length,const int *notes,const int *durations,float bpm,bool repeat)
+{
+    // copy arguments to member variables
+    _bpm = bpm;
+    _notes = notes;  // pointer for array
+    _durations = durations;  // pointer for array
+    _melody_length = length;
+    _repeat = repeat;
+
+    _note = 0;  // start from first note
+
+    play_next_note(); // play the next note in the melody
+}
+
+void Gamepad::write_dac(float val)
+{
+    if (val < 0.0f) {
+        val = 0.0f;
+    } else if (val > 1.0f) {
+        val = 1.0f;
+    }
+    dac->write(val);
+}
+
+
+void Gamepad::play_next_note()
+{
+    // _note is the note index to play
+
+    // calculate the duration and frequency of the note
+    float duration = 60.0f/(_bpm*_durations[_note]);
+    float frequency = float(_notes[_note]);
+    //printf("[%i] f = %f d = %f\n",_note,frequency,duration);
+
+    // check if the note is not a space and if not then play the note
+    if (frequency > 0) {
+        tone(frequency,duration);
+    }
+
+    // the timeout goes to the next note in the melody
+    // double the duration to leave a bit of a gap in between notes to be better
+    // able to distinguish them
+    note_timeout->attach(callback(this, &Gamepad::note_timeout_isr), duration*2.0f );
+}
+
+// called when the next note needs playing
+void Gamepad::note_timeout_isr()
+{
+    _note++; // go onto next note
+
+    // if in repeat mode then reset the note counter when get to end of melody
+    if (_repeat && _note == _melody_length) {
+        _note=0;
+    }
+
+    // check if note is within the melody
+    if (_note < _melody_length) {
+        play_next_note();
+    }
+}
+
+void Gamepad::ticker_isr()
+{
+    dac->write(_sample_array[_sample%_n]);  // use modulo to get index to play
+    _sample++;  // increment the sample ready for next time
+}
+
+void Gamepad::timeout_isr()
+{
+    // stops the ticker to end the note
+    ticker->detach();
+}