Diff: URF.cpp

Revision:

0:450a7208c682

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/URF.cpp	Tue May 03 08:02:58 2022 +0000
@@ -0,0 +1,74 @@
+#include "URF.h"
+
+#include "mbed.h"
+
+URF::URF(PinName URF_PIN)
+    : _event(URF_PIN)
+    , _cmd(URF_PIN)
+    , _timer()
+{
+    _event.rise(callback(this, &URF::_start));
+    _event.fall(callback(this, &URF::_stop));
+    _METER_PER_SECOND = 334.0;    // m/s
+    
+    _Busy = false;
+    
+    _cmd.output();
+    _cmd.write(0);
+    
+    _timer.stop();
+    _timer.reset();
+}
+
+void URF::_start(void)
+{
+//    _Valid = false;  // start the timere, and invalidate the current time.
+    _Busy = true;
+    _timer.reset();
+    _timer.start();
+}
+
+void URF::_stop(void)
+{
+//    _Valid = true;  // When it stops, update the time
+    _Busy = false;
+    _timer.stop();
+    _Time = _timer.read_us();
+}
+
+void URF::send(void)
+{
+    if(_Busy){
+        _timer.stop();
+        _Time = _timer.read_us();
+        return ;
+    }
+    _cmd.output();
+    _cmd.write(1);
+    wait_us(10);
+    _cmd.write(0);
+    _cmd.input();
+}
+
+void URF::Set_MpS(float MpS)
+{
+    _METER_PER_SECOND = MpS;
+}
+
+int URF::read(int scale)
+// -1 means not valid.
+{
+//    if(_Valid && ~_Busy)
+        return int(((_Time*(_METER_PER_SECOND / float(scale)))/2.0f) + 0.5f);
+//    else
+//        return -1;
+}
+
+int URF::read(void)
+// -1 means not valid.
+{
+//    if(_Valid && ~_Busy)
+        return int(((_Time*(_METER_PER_SECOND / 1000.0f))/2.0f) + 0.5f);
+//    else
+//        return -1;
+}
\ No newline at end of file