FRA221_2015 / Mbed 2 deprecated 8B_Bike_Light_Back

Important changes to repositories hosted on mbed.com

Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.

To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.

It is also possible to export all your personal repositories from the account settings page.

Dependencies:   mbed

Fork of 8B_Bike_Light_Back by Supakorn Meelarp

Diff: hcsr04.cpp

Revision:
0:b5bafad435c8
diff -r 000000000000 -r b5bafad435c8 hcsr04.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hcsr04.cpp	Wed Dec 09 10:15:06 2015 +0000
@@ -0,0 +1,29 @@
+#include "hcsr04.h"
+#include "mbed.h"
+/*
+*HCSR04.cpp
+*/
+HCSR04::HCSR04(PinName t, PinName e) : trig(t), echo(e) {}
+ long HCSR04::echo_duration() {
+        
+    timer.reset();  //reset timer
+    trig=0;   // trigger low 
+    wait_us(2); //  wait 
+    trig=1;   //  trigger high
+    wait_us(10);
+    trig=0;  // trigger low
+         while(!echo); // start pulseIN
+      timer.start();
+     while(echo);
+      timer.stop();
+     return timer.read_us(); 
+ 
+}
+ 
+//return distance in cm 
+long HCSR04::distance(){
+    duration = echo_duration();
+  distance_cm = (duration/2)/29.1  ;
+        return distance_cm;
+
+}
\ No newline at end of file