Diff: ultrasonic.cpp

Revision:

95:250afd53b710

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ultrasonic.cpp	Sat Jun 08 12:00:38 2019 +0000
@@ -0,0 +1,115 @@
+#include "ultrasonic.h"
+
+// generate a 10 us pulse to start HCSR04 ulrasonic sensor and
+// enable IRQ for echo pin.
+Ultrasonic::Ultrasonic(PinName trigPin, PinName echoPin, float timeout, bool mode, float time) :
+    _trig(trigPin), _echo(echoPin), _toVal(timeout), _pc(PA_2, PA_3), _repeat(mode), _repeatD(time){
+    _timer.reset();
+    _echo.rise(this, &Ultrasonic::_startT);
+    _echo.fall(this, &Ultrasonic::_endT);
+    _echo.mode(PullUp);
+    _echo.disable_irq();
+    _pc.baud(115200);
+}
+
+
+Ultrasonic::~Ultrasonic(){}
+
+int Ultrasonic::getDistance(void) {
+    calculateDistance();
+    return _distance;
+}
+
+void Ultrasonic::calculateDistance(void) {
+    clearStatus();
+
+    trig();
+    getPulseDuration();
+
+    if (_pulseDuration >= 0) _distance = _pulseDuration / 29 / 2;
+    else _distance = -1;
+    
+}
+
+void Ultrasonic::trig(void) {
+    _echo.enable_irq();
+    _trig = 1;
+    wait_us(10);
+    _trig = 0;
+}
+
+int Ultrasonic::getPulseDuration(void) {
+
+    while (!_break) {
+       _pc.printf("\r");
+    }  // wait signal
+    // we need to change 
+
+    _break = 0;
+    _echo.disable_irq();
+
+    if (_end >= 0) _pulseDuration = _end - _start;
+    else _pulseDuration = -1;
+    
+    return _pulseDuration;
+}
+
+int Ultrasonic::getStatus(void) {
+    return _done;
+}
+
+void Ultrasonic::clearStatus(void) {
+    _done          = 0;
+    _pulseDuration = 0;
+    _distance      = 0;
+    _start         = -1;
+    _end           = -1;
+    _trig          = 0;
+}
+
+void Ultrasonic::pauseMeasure(void) {
+    _done = 1;
+}
+
+void Ultrasonic::_startT(void) {
+    _timer.start();
+    _start = _timer.read_us();
+    _timeout.attach(callback(this, &Ultrasonic::_timeout_cb), _toVal);
+}
+
+void Ultrasonic::_endT(void) {
+    _timeout.detach();
+    _end = _timer.read_us();
+    _timer.stop();
+    _timer.reset();
+    _break = 1;
+}
+
+void Ultrasonic::_timeout_cb(void) {
+    _timer.stop();
+    _timer.reset();
+    _break = 1;
+}
+
+void Ultrasonic::setMode(bool mode){
+    _repeat = mode;
+}
+
+void Ultrasonic::printDistance(float interval){
+    
+    int num = (int)(1/interval);
+    
+    if(_repeat == true)
+    {
+        for(int i=0; i<num; i++)
+        {
+            _pc.printf("distance: %d\r\n", getDistance());
+            wait(interval/2);
+        }
+    }
+    
+    else
+        _pc.printf("distance: %d\r\n", getDistance());
+        
+    num = 0;
+}