The present code implements a single player squash game, using joystick to move paddle right or left. And checks the current temperature inside the device.
main.cpp
- Committer:
- eencae
- Date:
- 2015-03-08
- Revision:
- 0:026fa541af7a
File content as of revision 0:026fa541af7a:
/* Joystick Example code of how to read a joystick https://www.sparkfun.com/products/9032 Craig A. Evans 7 March 2015 */ #include "mbed.h" // change this to alter tolerance of joystick direction #define DIRECTION_TOLERANCE 0.05 // connections for joystick DigitalIn button(p18); AnalogIn xPot(p19); AnalogIn yPot(p20); // timer to regularly read the joystick Ticker pollJoystick; // Serial for debug Serial serial(USBTX,USBRX); // create enumerated type (0,1,2,3 etc. for direction) // could be extended for diagonals etc. enum DirectionName { UP, DOWN, LEFT, RIGHT, CENTRE, UNKNOWN }; // struct for Joystick typedef struct JoyStick Joystick; struct JoyStick { float x; // current x value float x0; // 'centred' x value float y; // current y value float y0; // 'centred' y value int button; // button state (assume pull-down used, so 1 = pressed, 0 = unpressed) DirectionName direction; // current direction }; // create struct variable Joystick joystick; int printFlag = 0; // function prototypes void calibrateJoystick(); void updateJoystick(); int main() { calibrateJoystick(); // get centred values of joystick pollJoystick.attach(&updateJoystick,1.0/10.0); // read joystick 10 times per second while(1) { if (printFlag) { // if flag set, clear flag and print joystick values to serial port printFlag = 0; serial.printf("x = %f y = %f button = %d ",joystick.x,joystick.y,joystick.button); // check joystick direction if (joystick.direction == UP) serial.printf(" UP\n"); if (joystick.direction == DOWN) serial.printf(" DOWN\n"); if (joystick.direction == LEFT) serial.printf(" LEFT\n"); if (joystick.direction == RIGHT) serial.printf(" RIGHT\n"); if (joystick.direction == CENTRE) serial.printf(" CENTRE\n"); if (joystick.direction == UNKNOWN) serial.printf(" Unsupported direction\n"); } } } // read default positions of the joystick to calibrate later readings void calibrateJoystick() { button.mode(PullDown); // must not move during calibration joystick.x0 = xPot; // initial positions in the range 0.0 to 1.0 (0.5 if centred exactly) joystick.y0 = yPot; } void updateJoystick() { // read current joystick values relative to calibrated values (in range -0.5 to 0.5, 0.0 is centred) joystick.x = xPot - joystick.x0; joystick.y = yPot - joystick.y0; // read button state joystick.button = button; // calculate direction depending on x,y values // tolerance allows a little lee-way in case joystick not exactly in the stated direction if ( fabs(joystick.y) < DIRECTION_TOLERANCE && fabs(joystick.x) < DIRECTION_TOLERANCE) { joystick.direction = CENTRE; } else if ( joystick.y > DIRECTION_TOLERANCE && fabs(joystick.x) < DIRECTION_TOLERANCE) { joystick.direction = UP; } else if ( joystick.y < DIRECTION_TOLERANCE && fabs(joystick.x) < DIRECTION_TOLERANCE) { joystick.direction = DOWN; } else if ( joystick.x > DIRECTION_TOLERANCE && fabs(joystick.y) < DIRECTION_TOLERANCE) { joystick.direction = RIGHT; } else if ( joystick.x < DIRECTION_TOLERANCE && fabs(joystick.y) < DIRECTION_TOLERANCE) { joystick.direction = LEFT; } else { joystick.direction = UNKNOWN; } // set flag for printing printFlag = 1; }