File content as of revision 0:3c59bc5c9388:

#ifndef IR_H
#define IR_H

#include "mbed.h"

extern Serial pc;

class IRSensor {
public:
    DigitalOut _enable;
    AnalogIn _input;
    volatile float value; 
    float COEFF_1;
    float COEFF_2;
    float COEFF_3;
    float COEFF_4;
    float COEFF_5;
    float COEFF_6;
    float COEFF_7;

    float last_read[5];
    
    IRSensor(PinName enable, PinName input, float c1 = 0.217722944294793f, float c2 = -5.50965509541424f, 
                        float c3 = 55.0111470003071f, float c4 = -229.934241342364f, float c5 = 506.986371752309f, 
                        float c6 = -502.862134567129f, float c7 = 177.712915019135f) : _enable(enable), _input(input), 
                        COEFF_1(c1), COEFF_2(c2), COEFF_3(c3), COEFF_4(c4), COEFF_5(c5), COEFF_6(c6), COEFF_7(c7) {
    }
    
    //Get the value in encoder units, samples?... 
    float readIR(){
        float sum = 0;

        //Each duration takes 100us, 5 times = 0.5ms
        for (int i = 0; i < 5; i++)
        {
            //Turn on IR LED tx
            _enable = 1;
    
            //Wait for capacitor to fire, 10us
            wait_us(6);
            
            last_read[i] = _input.read();
            if (i){
                sum += last_read[i];
            }
            //Wait 5us for turning off IR LED tx
            _enable = 0;
    
            //Wait 85us for turning on IR LED tx
            wait_us(75);
        }
        
        sum /= 4;
        value = sum;
        
        float square = sum * sum;
        float cube = square * sum;
        float _value = 0;
        _value += COEFF_1 / cube;
        _value += COEFF_2 / square;
        _value += COEFF_3 / sum;
        _value += COEFF_4;
        _value += COEFF_5 * sum;
        _value += COEFF_6 * square;
        _value += COEFF_7 * square * sum;
        
        return _value;
    }

    //Get the number of cells away wall is
    float cell_dist(){
        return readIR() / 18;
    }

    //Shorthand for read()
    operator float() {
        return readIR();
    }

};

extern IRSensor rightIR;
extern IRSensor rightDiagonalIR;
extern IRSensor rightFrontIR;
extern IRSensor leftFrontIR;
extern IRSensor leftDiagonalIR;
extern IRSensor leftIR;


#endif