RFSRF05.cpp

00001 
00002 #include "RFSRF05.h"
00003 #include "mbed.h"
00004 #include "globals.h"
00005 
00006 RFSRF05::RFSRF05(PinName trigger,
00007                  PinName echo0,
00008                  PinName echo1,
00009                  PinName echo2,
00010                  PinName echo3,
00011                  PinName echo4,
00012                  PinName echo5,
00013                  PinName SDI,
00014                  PinName SDO,
00015                  PinName SCK,
00016                  PinName NCS,
00017                  PinName NIRQ)
00018         : _rf(SDI,SDO,SCK,NCS,NIRQ),
00019         _trigger(trigger),
00020         _echo0(echo0),
00021         _echo1(echo1),
00022         _echo2(echo2),
00023         _echo3(echo3),
00024         _echo4(echo4),
00025         _echo5(echo5) {
00026         
00027     // initialises codes
00028     _code[0] = CODE0;
00029     _code[1] = CODE1;
00030     _code[2] = CODE2;
00031 
00032     //set callback execute to true
00033     ValidPulse = false;
00034 
00035     // Attach interrupts
00036     _echo0.rise(this, &RFSRF05::_rising);
00037     _echo0.fall(this, &RFSRF05::_falling);
00038     _echo1.fall(this, &RFSRF05::_falling);
00039     _echo2.fall(this, &RFSRF05::_falling);
00040     _echo3.fall(this, &RFSRF05::_falling);
00041     _echo4.fall(this, &RFSRF05::_falling);
00042     _echo5.fall(this, &RFSRF05::_falling);
00043 
00044 
00045     //init callabck function
00046     callbackfunc = NULL;
00047     callbackobj = NULL;
00048     mcallbackfunc = NULL;
00049 
00050     // innitialises beacon counter
00051     _beacon_counter = 0;
00052 
00053     //Interrupts every 50ms
00054     _ticker.attach(this, &RFSRF05::_startRange, 0.05);
00055 }
00056 
00057 
00058 void RFSRF05::_startRange() {
00059 
00060     //printf("Srange\r\r");
00061 
00062     // increments counter
00063     _beacon_counter = (_beacon_counter + 1) % 3;
00064 
00065 
00066     // set flags
00067     ValidPulse = false;
00068     expValidPulse = true;
00069 
00070     // writes code to RF port
00071     _rf.write(_code[_beacon_counter]);
00072     
00073 
00074 
00075     // send a trigger pulse, 10uS long
00076     _trigger = 1;
00077     wait_us (10);
00078     _trigger = 0;
00079 
00080 }
00081 
00082 
00083 // Clear and start the timer at the begining of the echo pulse
00084 void RFSRF05::_rising(void) {
00085 
00086     _timer.reset();
00087     _timer.start();
00088     
00089     //Set callback execute to ture
00090     if (expValidPulse) {
00091         ValidPulse = true;
00092         expValidPulse = false;
00093     }
00094 }
00095 
00096 // Stop and read the timer at the end of the pulse
00097 void RFSRF05::_falling(void) {
00098     _timer.stop();
00099 
00100     if (ValidPulse) {
00101         //printf("Validpulse trig!\r\n");
00102         ValidPulse = false;
00103 
00104         //Calucate distance
00105         _dist[_beacon_counter] =  _timer.read_us()/2.9 + 300;
00106 
00107         if (callbackfunc)
00108             (*callbackfunc)(_beacon_counter, _dist[_beacon_counter]);
00109 
00110         if (callbackobj && mcallbackfunc)
00111             (callbackobj->*mcallbackfunc)(_beacon_counter, _dist[_beacon_counter], sonarvariance);
00112 
00113     }
00114 
00115 }
00116 
00117 float RFSRF05::read0() {
00118     // returns distance
00119     return (_dist[0]);
00120 }
00121 
00122 float RFSRF05::read1() {
00123     // returns distance
00124     return (_dist[1]);
00125 }
00126 
00127 float RFSRF05::read2() {
00128     // returns distance
00129     return (_dist[2]);
00130 }
00131 
00132 float RFSRF05::read(unsigned int beaconnum) {
00133     // returns distance
00134     return (_dist[beaconnum]);
00135 }
00136 
00137 //SRF05::operator float() {
00138 //    return read();
00139 //}