Diff: HCSR04.cpp

Revision:

1:d388301a0227

Parent:

0:0bda99bb39a4

--- a/HCSR04.cpp	Tue Oct 18 14:32:12 2011 +0000
+++ b/HCSR04.cpp	Mon May 26 14:10:33 2014 +0000
@@ -7,13 +7,14 @@
 //      Trigger          Echo
 //      _______           _____________,,,,,,,,,
 // ____|  10us |_________| 150us-25ms, or 38ms if no obstacle
-// 
+//
 
 //return echo duration in us (refer to digram above)
-long HCSR04::echo_duration() {
+int HCSR04::echo_duration()
+{
     timer.reset();
     trig = 0;
-    wait_us(2);
+    wait_us(10);
     trig = 1;
     wait_us(10);
     trig = 0;
@@ -24,15 +25,14 @@
     return timer.read_us();
 }
 
-//return distance to nearest obstacle or returns -1 
+//return distance to nearest obstacle or returns -1
 //if no obstacle within range
 //set sys to cm or inch accordingly
-long HCSR04::distance(int sys){
+int HCSR04::distance(int sys)
+{
     duration = echo_duration();
-    if(duration > 30000)
-        return -1;
-    distacne_cm = duration /29 / 2 ;
-    distance_inc = duration / 74 / 2;
+    distacne_cm = duration  /29/2;
+    distance_inc = duration /74/2;
     if (sys)
         return distacne_cm;
     else