RFSRF05.cpp

Committer:
narshu
Date:
2012-03-30
Revision:
0:7583de124698
Child:
1:0370ea94b64a

File content as of revision 0:7583de124698:


#include "RFSRF05.h"
#include "mbed.h"



RFSRF05::RFSRF05(PinName trigger,
                 PinName echo0,
                 PinName echo1,
                 PinName echo2,
                 PinName echo3,
                 PinName echo4,
                 PinName echo5,
                 PinName SDI,
                 PinName SDO,
                 PinName SCK,
                 PinName NCS,
                 PinName NIRQ)
        : _rf(SDI,SDO,SCK,NCS,NIRQ),
        _trigger(trigger),
        _echo0(echo0),
        _echo1(echo1),
        _echo2(echo2),
        _echo3(echo3),
        _echo4(echo4),
        _echo5(echo5) {
    // initialises codes
    _code[0] = CODE0;
    _code[1] = CODE1;
    _code[2] = CODE2;

    //set callback execute to true
    ValidPulse = false;

    // Attach interrupts
    _echo0.rise(this, &RFSRF05::_rising);
    _echo0.fall(this, &RFSRF05::_falling);
    _echo1.fall(this, &RFSRF05::_falling);
    _echo2.fall(this, &RFSRF05::_falling);
    _echo3.fall(this, &RFSRF05::_falling);
    _echo4.fall(this, &RFSRF05::_falling);
    _echo5.fall(this, &RFSRF05::_falling);


    //init callabck function
    callbackfunc = NULL;
    callbackobj = NULL;
    mcallbackfunc = NULL;

    // innitialises beacon counter
    _beacon_counter = 0;

    //Interrupts every 50ms
    //_ticker.attach(this, &RFSRF05::_startRange, 0.05);
}


void RFSRF05::startRange() {

    //printf("Srange\r\r");

    // increments counter
    _beacon_counter = (_beacon_counter + 1) % 3;

    // writes code to RF port
    _rf.write(_code[_beacon_counter]);

    // send a trigger pulse, 10uS long
    ValidPulse = false;
    expValidPulse = true;

    _trigger = 1;
    wait_us (10);
    _trigger = 0;
    wait_us(50);
}


// Clear and start the timer at the begining of the echo pulse
void RFSRF05::_rising(void) {

    _timer.reset();
    _timer.start();

    //Set callback execute to ture
    if (expValidPulse) {
        ValidPulse = true;
        expValidPulse = false;
    }
}

// Stop and read the timer at the end of the pulse
void RFSRF05::_falling(void) {
    _timer.stop();

    if (ValidPulse) {
        //printf("Validpulse trig!\r\n");
        ValidPulse = false;

        //Calucate distance
        _dist[_beacon_counter] =  _timer.read_us()/2.9 + 300;

        if (callbackfunc)
            (*callbackfunc)(_beacon_counter, _dist[_beacon_counter]);

        if (callbackobj && mcallbackfunc)
            (callbackobj->*mcallbackfunc)(_beacon_counter, _dist[_beacon_counter]);

    }

}

float RFSRF05::read0() {
    // returns distance
    return (_dist[0]);
}

float RFSRF05::read1() {
    // returns distance
    return (_dist[1]);
}

float RFSRF05::read2() {
    // returns distance
    return (_dist[2]);
}

float RFSRF05::read(unsigned int beaconnum) {
    // returns distance
    return (_dist[beaconnum]);
}

//SRF05::operator float() {
//    return read();
//}