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Dependencies:   mbed

Gamepad/Gamepad.cpp@0:1a1863a687d3, 2018-04-17 (annotated)

Committer:
el16a2t
Date:
Tue Apr 17 08:33:39 2018 +0000
Revision:
0:1a1863a687d3
initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
el16a2t 0:1a1863a687d3 1 #include "Gamepad.h"
el16a2t 0:1a1863a687d3 2
el16a2t 0:1a1863a687d3 3 #include "mbed.h"
el16a2t 0:1a1863a687d3 4
el16a2t 0:1a1863a687d3 5 //////////// constructor/destructor ////////////
el16a2t 0:1a1863a687d3 6 Gamepad::Gamepad()
el16a2t 0:1a1863a687d3 7 :
el16a2t 0:1a1863a687d3 8 _led1(new PwmOut(PTA1)),
el16a2t 0:1a1863a687d3 9 _led2(new PwmOut(PTA2)),
el16a2t 0:1a1863a687d3 10 _led3(new PwmOut(PTC2)),
el16a2t 0:1a1863a687d3 11 _led4(new PwmOut(PTC3)),
el16a2t 0:1a1863a687d3 12 _led5(new PwmOut(PTC4)),
el16a2t 0:1a1863a687d3 13 _led6(new PwmOut(PTD3)),
el16a2t 0:1a1863a687d3 14
el16a2t 0:1a1863a687d3 15 _button_A(new InterruptIn(PTB9)),
el16a2t 0:1a1863a687d3 16 _button_B(new InterruptIn(PTD0)),
el16a2t 0:1a1863a687d3 17 _button_X(new InterruptIn(PTC17)),
el16a2t 0:1a1863a687d3 18 _button_Y(new InterruptIn(PTC12)),
el16a2t 0:1a1863a687d3 19 _button_L(new InterruptIn(PTB18)),
el16a2t 0:1a1863a687d3 20 _button_R(new InterruptIn(PTB3)),
el16a2t 0:1a1863a687d3 21 _button_back(new InterruptIn(PTB19)),
el16a2t 0:1a1863a687d3 22 _button_start(new InterruptIn(PTC5)),
el16a2t 0:1a1863a687d3 23 _button_joystick(new InterruptIn(PTC16)),
el16a2t 0:1a1863a687d3 24
el16a2t 0:1a1863a687d3 25 _vert(new AnalogIn(PTB10)),
el16a2t 0:1a1863a687d3 26 _horiz(new AnalogIn(PTB11)),
el16a2t 0:1a1863a687d3 27
el16a2t 0:1a1863a687d3 28 _buzzer(new PwmOut(PTC10)),
el16a2t 0:1a1863a687d3 29 _pot(new AnalogIn(PTB2)),
el16a2t 0:1a1863a687d3 30
el16a2t 0:1a1863a687d3 31 _timeout(new Timeout()),
el16a2t 0:1a1863a687d3 32
el16a2t 0:1a1863a687d3 33 _event_state(0),
el16a2t 0:1a1863a687d3 34
el16a2t 0:1a1863a687d3 35 _x0(0),
el16a2t 0:1a1863a687d3 36 _y0(0)
el16a2t 0:1a1863a687d3 37 {}
el16a2t 0:1a1863a687d3 38
el16a2t 0:1a1863a687d3 39 Gamepad::~Gamepad()
el16a2t 0:1a1863a687d3 40 {
el16a2t 0:1a1863a687d3 41 delete _led1,_led2,_led3,_led4,_led5,_led6;
el16a2t 0:1a1863a687d3 42 delete _button_A,_button_B,_button_joystick,_vert,_horiz;
el16a2t 0:1a1863a687d3 43 delete _button_X,_button_Y,_button_back,_button_start;
el16a2t 0:1a1863a687d3 44 delete _button_L,_button_R, _buzzer, _pot, _timeout;
el16a2t 0:1a1863a687d3 45 }
el16a2t 0:1a1863a687d3 46
el16a2t 0:1a1863a687d3 47 ///////////////// public methods /////////////////
el16a2t 0:1a1863a687d3 48
el16a2t 0:1a1863a687d3 49 void Gamepad::init()
el16a2t 0:1a1863a687d3 50 {
el16a2t 0:1a1863a687d3 51 leds_off();
el16a2t 0:1a1863a687d3 52 init_buttons();
el16a2t 0:1a1863a687d3 53
el16a2t 0:1a1863a687d3 54 // read centred values of joystick
el16a2t 0:1a1863a687d3 55 _x0 = _horiz->read();
el16a2t 0:1a1863a687d3 56 _y0 = _vert->read();
el16a2t 0:1a1863a687d3 57
el16a2t 0:1a1863a687d3 58 // clear all flags
el16a2t 0:1a1863a687d3 59 _event_state = 0;
el16a2t 0:1a1863a687d3 60 }
el16a2t 0:1a1863a687d3 61
el16a2t 0:1a1863a687d3 62 void Gamepad::leds_off()
el16a2t 0:1a1863a687d3 63 {
el16a2t 0:1a1863a687d3 64 leds(0.0);
el16a2t 0:1a1863a687d3 65 }
el16a2t 0:1a1863a687d3 66
el16a2t 0:1a1863a687d3 67 void Gamepad::leds_on()
el16a2t 0:1a1863a687d3 68 {
el16a2t 0:1a1863a687d3 69 leds(1.0);
el16a2t 0:1a1863a687d3 70 }
el16a2t 0:1a1863a687d3 71
el16a2t 0:1a1863a687d3 72 void Gamepad::leds(float val) const
el16a2t 0:1a1863a687d3 73 {
el16a2t 0:1a1863a687d3 74 if (val < 0.0f) {
el16a2t 0:1a1863a687d3 75 val = 0.0f;
el16a2t 0:1a1863a687d3 76 }
el16a2t 0:1a1863a687d3 77 if (val > 1.0f) {
el16a2t 0:1a1863a687d3 78 val = 1.0f;
el16a2t 0:1a1863a687d3 79 }
el16a2t 0:1a1863a687d3 80
el16a2t 0:1a1863a687d3 81 // leds are active-low, so subtract from 1.0
el16a2t 0:1a1863a687d3 82 // 0.0 corresponds to fully-off, 1.0 to fully-on
el16a2t 0:1a1863a687d3 83 val = 1.0f - val;
el16a2t 0:1a1863a687d3 84
el16a2t 0:1a1863a687d3 85 _led1->write(val);
el16a2t 0:1a1863a687d3 86 _led2->write(val);
el16a2t 0:1a1863a687d3 87 _led3->write(val);
el16a2t 0:1a1863a687d3 88 _led4->write(val);
el16a2t 0:1a1863a687d3 89 _led5->write(val);
el16a2t 0:1a1863a687d3 90 _led6->write(val);
el16a2t 0:1a1863a687d3 91 }
el16a2t 0:1a1863a687d3 92
el16a2t 0:1a1863a687d3 93 void Gamepad::led(int n,float val) const
el16a2t 0:1a1863a687d3 94 {
el16a2t 0:1a1863a687d3 95 // ensure they are within vlaid range
el16a2t 0:1a1863a687d3 96 if (val < 0.0f) {
el16a2t 0:1a1863a687d3 97 val = 0.0f;
el16a2t 0:1a1863a687d3 98 }
el16a2t 0:1a1863a687d3 99 if (val > 1.0f) {
el16a2t 0:1a1863a687d3 100 val = 1.0f;
el16a2t 0:1a1863a687d3 101 }
el16a2t 0:1a1863a687d3 102
el16a2t 0:1a1863a687d3 103 switch (n) {
el16a2t 0:1a1863a687d3 104
el16a2t 0:1a1863a687d3 105 // check for valid LED number and set value
el16a2t 0:1a1863a687d3 106
el16a2t 0:1a1863a687d3 107 case 1:
el16a2t 0:1a1863a687d3 108 _led1->write(1.0f-val); // active-low so subtract from 1
el16a2t 0:1a1863a687d3 109 break;
el16a2t 0:1a1863a687d3 110 case 2:
el16a2t 0:1a1863a687d3 111 _led2->write(1.0f-val); // active-low so subtract from 1
el16a2t 0:1a1863a687d3 112 break;
el16a2t 0:1a1863a687d3 113 case 3:
el16a2t 0:1a1863a687d3 114 _led3->write(1.0f-val); // active-low so subtract from 1
el16a2t 0:1a1863a687d3 115 break;
el16a2t 0:1a1863a687d3 116 case 4:
el16a2t 0:1a1863a687d3 117 _led4->write(1.0f-val); // active-low so subtract from 1
el16a2t 0:1a1863a687d3 118 break;
el16a2t 0:1a1863a687d3 119 case 5:
el16a2t 0:1a1863a687d3 120 _led5->write(1.0f-val); // active-low so subtract from 1
el16a2t 0:1a1863a687d3 121 break;
el16a2t 0:1a1863a687d3 122 case 6:
el16a2t 0:1a1863a687d3 123 _led6->write(1.0f-val); // active-low so subtract from 1
el16a2t 0:1a1863a687d3 124 break;
el16a2t 0:1a1863a687d3 125
el16a2t 0:1a1863a687d3 126 }
el16a2t 0:1a1863a687d3 127 }
el16a2t 0:1a1863a687d3 128
el16a2t 0:1a1863a687d3 129 float Gamepad::read_pot() const
el16a2t 0:1a1863a687d3 130 {
el16a2t 0:1a1863a687d3 131 return _pot->read();
el16a2t 0:1a1863a687d3 132 }
el16a2t 0:1a1863a687d3 133
el16a2t 0:1a1863a687d3 134 void Gamepad::tone(float frequency, float duration)
el16a2t 0:1a1863a687d3 135 {
el16a2t 0:1a1863a687d3 136 _buzzer->period(1.0f/frequency);
el16a2t 0:1a1863a687d3 137 _buzzer->write(0.5); // 50% duty cycle - square wave
el16a2t 0:1a1863a687d3 138 _timeout->attach(callback(this, &Gamepad::tone_off), duration );
el16a2t 0:1a1863a687d3 139 }
el16a2t 0:1a1863a687d3 140
el16a2t 0:1a1863a687d3 141 bool Gamepad::check_event(GamepadEvent const id)
el16a2t 0:1a1863a687d3 142 {
el16a2t 0:1a1863a687d3 143 // Check whether event flag is set
el16a2t 0:1a1863a687d3 144 if (_event_state[id]) {
el16a2t 0:1a1863a687d3 145 _event_state.reset(id); // clear flag
el16a2t 0:1a1863a687d3 146 return true;
el16a2t 0:1a1863a687d3 147 } else {
el16a2t 0:1a1863a687d3 148 return false;
el16a2t 0:1a1863a687d3 149 }
el16a2t 0:1a1863a687d3 150 }
el16a2t 0:1a1863a687d3 151
el16a2t 0:1a1863a687d3 152 // this method gets the magnitude of the joystick movement
el16a2t 0:1a1863a687d3 153 float Gamepad::get_mag()
el16a2t 0:1a1863a687d3 154 {
el16a2t 0:1a1863a687d3 155 Polar p = get_polar();
el16a2t 0:1a1863a687d3 156 return p.mag;
el16a2t 0:1a1863a687d3 157 }
el16a2t 0:1a1863a687d3 158
el16a2t 0:1a1863a687d3 159 // this method gets the angle of joystick movement (0 to 360, 0 North)
el16a2t 0:1a1863a687d3 160 float Gamepad::get_angle()
el16a2t 0:1a1863a687d3 161 {
el16a2t 0:1a1863a687d3 162 Polar p = get_polar();
el16a2t 0:1a1863a687d3 163 return p.angle;
el16a2t 0:1a1863a687d3 164 }
el16a2t 0:1a1863a687d3 165
el16a2t 0:1a1863a687d3 166 Direction Gamepad::get_direction()
el16a2t 0:1a1863a687d3 167 {
el16a2t 0:1a1863a687d3 168 float angle = get_angle(); // 0 to 360, -1 for centred
el16a2t 0:1a1863a687d3 169
el16a2t 0:1a1863a687d3 170 Direction d;
el16a2t 0:1a1863a687d3 171 // partition 360 into segments and check which segment the angle is in
el16a2t 0:1a1863a687d3 172 if (angle < 0.0f) {
el16a2t 0:1a1863a687d3 173 d = CENTRE; // check for -1.0 angle
el16a2t 0:1a1863a687d3 174 } else if (angle < 22.5f) { // then keep going in 45 degree increments
el16a2t 0:1a1863a687d3 175 d = N;
el16a2t 0:1a1863a687d3 176 } else if (angle < 67.5f) {
el16a2t 0:1a1863a687d3 177 d = NE;
el16a2t 0:1a1863a687d3 178 } else if (angle < 112.5f) {
el16a2t 0:1a1863a687d3 179 d = E;
el16a2t 0:1a1863a687d3 180 } else if (angle < 157.5f) {
el16a2t 0:1a1863a687d3 181 d = SE;
el16a2t 0:1a1863a687d3 182 } else if (angle < 202.5f) {
el16a2t 0:1a1863a687d3 183 d = S;
el16a2t 0:1a1863a687d3 184 } else if (angle < 247.5f) {
el16a2t 0:1a1863a687d3 185 d = SW;
el16a2t 0:1a1863a687d3 186 } else if (angle < 292.5f) {
el16a2t 0:1a1863a687d3 187 d = W;
el16a2t 0:1a1863a687d3 188 } else if (angle < 337.5f) {
el16a2t 0:1a1863a687d3 189 d = NW;
el16a2t 0:1a1863a687d3 190 } else {
el16a2t 0:1a1863a687d3 191 d = N;
el16a2t 0:1a1863a687d3 192 }
el16a2t 0:1a1863a687d3 193
el16a2t 0:1a1863a687d3 194 return d;
el16a2t 0:1a1863a687d3 195 }
el16a2t 0:1a1863a687d3 196
el16a2t 0:1a1863a687d3 197 ///////////////////// private methods ////////////////////////
el16a2t 0:1a1863a687d3 198
el16a2t 0:1a1863a687d3 199 void Gamepad::tone_off()
el16a2t 0:1a1863a687d3 200 {
el16a2t 0:1a1863a687d3 201 // called after timeout
el16a2t 0:1a1863a687d3 202 _buzzer->write(0.0);
el16a2t 0:1a1863a687d3 203 }
el16a2t 0:1a1863a687d3 204
el16a2t 0:1a1863a687d3 205 void Gamepad::init_buttons()
el16a2t 0:1a1863a687d3 206 {
el16a2t 0:1a1863a687d3 207 // turn on pull-downs as other side of button is connected to 3V3
el16a2t 0:1a1863a687d3 208 // button is 0 when not pressed and 1 when pressed
el16a2t 0:1a1863a687d3 209 _button_A->mode(PullDown);
el16a2t 0:1a1863a687d3 210 _button_B->mode(PullDown);
el16a2t 0:1a1863a687d3 211 _button_X->mode(PullDown);
el16a2t 0:1a1863a687d3 212 _button_Y->mode(PullDown);
el16a2t 0:1a1863a687d3 213 _button_back->mode(PullDown);
el16a2t 0:1a1863a687d3 214 _button_start->mode(PullDown);
el16a2t 0:1a1863a687d3 215 _button_L->mode(PullDown);
el16a2t 0:1a1863a687d3 216 _button_R->mode(PullDown);
el16a2t 0:1a1863a687d3 217 _button_joystick->mode(PullDown);
el16a2t 0:1a1863a687d3 218 // therefore setup rising edge interrupts
el16a2t 0:1a1863a687d3 219 _button_A->rise(callback(this,&Gamepad::a_isr));
el16a2t 0:1a1863a687d3 220 _button_B->rise(callback(this,&Gamepad::b_isr));
el16a2t 0:1a1863a687d3 221 _button_X->rise(callback(this,&Gamepad::x_isr));
el16a2t 0:1a1863a687d3 222 _button_Y->rise(callback(this,&Gamepad::y_isr));
el16a2t 0:1a1863a687d3 223 _button_L->rise(callback(this,&Gamepad::l_isr));
el16a2t 0:1a1863a687d3 224 _button_R->rise(callback(this,&Gamepad::r_isr));
el16a2t 0:1a1863a687d3 225 _button_start->rise(callback(this,&Gamepad::start_isr));
el16a2t 0:1a1863a687d3 226 _button_back->rise(callback(this,&Gamepad::back_isr));
el16a2t 0:1a1863a687d3 227 _button_joystick->rise(callback(this,&Gamepad::joy_isr));
el16a2t 0:1a1863a687d3 228 }
el16a2t 0:1a1863a687d3 229
el16a2t 0:1a1863a687d3 230 // button interrupts ISRs
el16a2t 0:1a1863a687d3 231 // Each of these simply sets the appropriate event bit in the _event_state
el16a2t 0:1a1863a687d3 232 // variable
el16a2t 0:1a1863a687d3 233 void Gamepad::a_isr()
el16a2t 0:1a1863a687d3 234 {
el16a2t 0:1a1863a687d3 235 _event_state.set(A_PRESSED);
el16a2t 0:1a1863a687d3 236 }
el16a2t 0:1a1863a687d3 237 void Gamepad::b_isr()
el16a2t 0:1a1863a687d3 238 {
el16a2t 0:1a1863a687d3 239 _event_state.set(B_PRESSED);
el16a2t 0:1a1863a687d3 240 }
el16a2t 0:1a1863a687d3 241 void Gamepad::x_isr()
el16a2t 0:1a1863a687d3 242 {
el16a2t 0:1a1863a687d3 243 _event_state.set(X_PRESSED);
el16a2t 0:1a1863a687d3 244 }
el16a2t 0:1a1863a687d3 245 void Gamepad::y_isr()
el16a2t 0:1a1863a687d3 246 {
el16a2t 0:1a1863a687d3 247 _event_state.set(Y_PRESSED);
el16a2t 0:1a1863a687d3 248 }
el16a2t 0:1a1863a687d3 249 void Gamepad::l_isr()
el16a2t 0:1a1863a687d3 250 {
el16a2t 0:1a1863a687d3 251 _event_state.set(L_PRESSED);
el16a2t 0:1a1863a687d3 252 }
el16a2t 0:1a1863a687d3 253 void Gamepad::r_isr()
el16a2t 0:1a1863a687d3 254 {
el16a2t 0:1a1863a687d3 255 _event_state.set(R_PRESSED);
el16a2t 0:1a1863a687d3 256 }
el16a2t 0:1a1863a687d3 257 void Gamepad::back_isr()
el16a2t 0:1a1863a687d3 258 {
el16a2t 0:1a1863a687d3 259 _event_state.set(BACK_PRESSED);
el16a2t 0:1a1863a687d3 260 }
el16a2t 0:1a1863a687d3 261 void Gamepad::start_isr()
el16a2t 0:1a1863a687d3 262 {
el16a2t 0:1a1863a687d3 263 _event_state.set(START_PRESSED);
el16a2t 0:1a1863a687d3 264 }
el16a2t 0:1a1863a687d3 265 void Gamepad::joy_isr()
el16a2t 0:1a1863a687d3 266 {
el16a2t 0:1a1863a687d3 267 _event_state.set(JOY_PRESSED);
el16a2t 0:1a1863a687d3 268 }
el16a2t 0:1a1863a687d3 269
el16a2t 0:1a1863a687d3 270 // get raw joystick coordinate in range -1 to 1
el16a2t 0:1a1863a687d3 271 // Direction (x,y)
el16a2t 0:1a1863a687d3 272 // North (0,1)
el16a2t 0:1a1863a687d3 273 // East (1,0)
el16a2t 0:1a1863a687d3 274 // South (0,-1)
el16a2t 0:1a1863a687d3 275 // West (-1,0)
el16a2t 0:1a1863a687d3 276 Vector2D Gamepad::get_coord()
el16a2t 0:1a1863a687d3 277 {
el16a2t 0:1a1863a687d3 278 // read() returns value in range 0.0 to 1.0 so is scaled and centre value
el16a2t 0:1a1863a687d3 279 // substracted to get values in the range -1.0 to 1.0
el16a2t 0:1a1863a687d3 280 float x = 2.0f*( _horiz->read() - _x0 );
el16a2t 0:1a1863a687d3 281 float y = 2.0f*( _vert->read() - _y0 );
el16a2t 0:1a1863a687d3 282
el16a2t 0:1a1863a687d3 283 // Note: the x value here is inverted to ensure the positive x is to the
el16a2t 0:1a1863a687d3 284 // right. This is simply due to how the potentiometer on the joystick
el16a2t 0:1a1863a687d3 285 // I was using was connected up. It could have been corrected in hardware
el16a2t 0:1a1863a687d3 286 // by swapping the power supply pins. Instead it is done in software so may
el16a2t 0:1a1863a687d3 287 // need to be changed depending on your wiring setup
el16a2t 0:1a1863a687d3 288
el16a2t 0:1a1863a687d3 289 Vector2D coord = {-x,y};
el16a2t 0:1a1863a687d3 290 return coord;
el16a2t 0:1a1863a687d3 291 }
el16a2t 0:1a1863a687d3 292
el16a2t 0:1a1863a687d3 293 // This maps the raw x,y coord onto a circular grid.
el16a2t 0:1a1863a687d3 294 // See: http://mathproofs.blogspot.co.uk/2005/07/mapping-square-to-circle.html
el16a2t 0:1a1863a687d3 295 Vector2D Gamepad::get_mapped_coord()
el16a2t 0:1a1863a687d3 296 {
el16a2t 0:1a1863a687d3 297 Vector2D coord = get_coord();
el16a2t 0:1a1863a687d3 298
el16a2t 0:1a1863a687d3 299 // do the transformation
el16a2t 0:1a1863a687d3 300 float x = coord.x*sqrt(1.0f-pow(coord.y,2.0f)/2.0f);
el16a2t 0:1a1863a687d3 301 float y = coord.y*sqrt(1.0f-pow(coord.x,2.0f)/2.0f);
el16a2t 0:1a1863a687d3 302
el16a2t 0:1a1863a687d3 303 Vector2D mapped_coord = {x,y};
el16a2t 0:1a1863a687d3 304 return mapped_coord;
el16a2t 0:1a1863a687d3 305 }
el16a2t 0:1a1863a687d3 306
el16a2t 0:1a1863a687d3 307 // this function converts the mapped coordinates into polar form
el16a2t 0:1a1863a687d3 308 Polar Gamepad::get_polar()
el16a2t 0:1a1863a687d3 309 {
el16a2t 0:1a1863a687d3 310 // get the mapped coordinate
el16a2t 0:1a1863a687d3 311 Vector2D coord = get_mapped_coord();
el16a2t 0:1a1863a687d3 312
el16a2t 0:1a1863a687d3 313 // at this point, 0 degrees (i.e. x-axis) will be defined to the East.
el16a2t 0:1a1863a687d3 314 // We want 0 degrees to correspond to North and increase clockwise to 359
el16a2t 0:1a1863a687d3 315 // like a compass heading, so we need to swap the axis and invert y
el16a2t 0:1a1863a687d3 316 float x = coord.y;
el16a2t 0:1a1863a687d3 317 float y = coord.x;
el16a2t 0:1a1863a687d3 318
el16a2t 0:1a1863a687d3 319 float mag = sqrt(x*x+y*y); // pythagoras
el16a2t 0:1a1863a687d3 320 float angle = RAD2DEG*atan2(y,x);
el16a2t 0:1a1863a687d3 321 // angle will be in range -180 to 180, so add 360 to negative angles to
el16a2t 0:1a1863a687d3 322 // move to 0 to 360 range
el16a2t 0:1a1863a687d3 323 if (angle < 0.0f) {
el16a2t 0:1a1863a687d3 324 angle+=360.0f;
el16a2t 0:1a1863a687d3 325 }
el16a2t 0:1a1863a687d3 326
el16a2t 0:1a1863a687d3 327 // the noise on the ADC causes the values of x and y to fluctuate slightly
el16a2t 0:1a1863a687d3 328 // around the centred values. This causes the random angle values to get
el16a2t 0:1a1863a687d3 329 // calculated when the joystick is centred and untouched. This is also when
el16a2t 0:1a1863a687d3 330 // the magnitude is very small, so we can check for a small magnitude and then
el16a2t 0:1a1863a687d3 331 // set the angle to -1. This will inform us when the angle is invalid and the
el16a2t 0:1a1863a687d3 332 // joystick is centred
el16a2t 0:1a1863a687d3 333
el16a2t 0:1a1863a687d3 334 if (mag < TOL) {
el16a2t 0:1a1863a687d3 335 mag = 0.0f;
el16a2t 0:1a1863a687d3 336 angle = -1.0f;
el16a2t 0:1a1863a687d3 337 }
el16a2t 0:1a1863a687d3 338
el16a2t 0:1a1863a687d3 339 Polar p = {mag,angle};
el16a2t 0:1a1863a687d3 340 return p;
el16a2t 0:1a1863a687d3 341 }