Revision 1:b30b99a74f6e, committed 2022-05-08

Comitter:

sas638

Date:

Sun May 08 20:09:39 2022 +0000

Parent:

0:0bda99bb39a4

Commit message:

sensor;

Changed in this revision

diff -r 0bda99bb39a4 -r b30b99a74f6e HCSR04.cpp
--- a/HCSR04.cpp	Tue Oct 18 14:32:12 2011 +0000
+++ b/HCSR04.cpp	Sun May 08 20:09:39 2022 +0000
@@ -10,24 +10,24 @@
 // 
 
 //return echo duration in us (refer to digram above)
-long HCSR04::echo_duration() {
+int HCSR04::echo_duration() {
     timer.reset();
-    trig = 0;
-    wait_us(2);
-    trig = 1;
-    wait_us(10);
-    trig = 0;
-    while(echo == 0);
-    timer.start();
-    while(echo == 1);
-    timer.stop();
-    return timer.read_us();
+    trig = 0; //set trig low
+    wait_us(2); //wait 2 microseconds
+    trig = 1; //set trig high
+    wait_us(10); //wait 10 microseconds
+    trig = 0; // set trig low again
+    while(echo == 0); //while loop for starting timer when echo set to 0
+    timer.start(); //start timer
+    while(echo == 1); //while loop for stopping timer when echo set to 1
+    timer.stop(); // stop timer
+    return static_cast<int>(timer.read_us()); //return the timer 
 }
 
 //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;

diff -r 0bda99bb39a4 -r b30b99a74f6e HCSR04.h
--- a/HCSR04.h	Tue Oct 18 14:32:12 2011 +0000
+++ b/HCSR04.h	Sun May 08 20:09:39 2022 +0000
@@ -26,14 +26,14 @@
 class HCSR04 {
   public:
     HCSR04(PinName t, PinName e);
-    long echo_duration();
-    long distance(int sys);
+    int echo_duration();
+    int distance(int sys);
 
     private:
         DigitalOut trig;
         DigitalIn echo;
         Timer timer;
-        long duration,distacne_cm,distance_inc;
+        int duration,distacne_cm,distance_inc;
 };
 
 #endif
\ No newline at end of file