Revision 8:0fda00df4357, committed 2018-09-22

Comitter:

tektomo

Date:

Sat Sep 22 11:00:29 2018 +0000

Parent:

7:71da0dbf4400

Commit message:

????????

Changed in this revision

--- a/hcsr04.cpp	Sat Mar 30 18:55:03 2013 +0000
+++ b/hcsr04.cpp	Sat Sep 22 11:00:29 2018 +0000
@@ -18,12 +18,17 @@
  */
 
 
+
+
 #include "hcsr04.h"
 
 
+
+
 HCSR04::HCSR04(PinName TrigPin,PinName EchoPin):
     trigger(TrigPin), echo(EchoPin)
 {
+    setTemp(15);
     pulsetime.stop();
     pulsetime.reset();
     echo.rise(this,&HCSR04::isr_rise);
@@ -31,29 +36,48 @@
     trigger=0;
 }
 
+
 HCSR04::~HCSR04()
 {
 }
 
+
+void HCSR04::start(void)
+{
+    pulsetime_us = pulsetime.read_us();
+    if(pulsetime_us > maxTime){
+        pulsetime.stop();
+        pulsetime.reset();
+        trigger=1;
+        trigger=0;
+    }
+    trigger=1;
+    wait_us(10);
+    trigger=0;
+}
+
+
 void HCSR04::isr_rise(void)
 {
     pulsetime.start();
 }
-void HCSR04::start(void)
-{
-    trigger=1;
-    wait_us(10);
-    trigger=0;
-}
+
 
 void HCSR04::isr_fall(void)
 {
     pulsetime.stop();
-    pulsedur = pulsetime.read_us();
-    distance= (pulsedur*343)/20000;
+    pulsetime_us = pulsetime.read_us();
+    if(pulsetime_us > maxTime){
+        trigger=1;
+        trigger=0;
+        distance = 0;
+    }else{
+    distance = pulsetime_us*sonic/20000;
+    }
     pulsetime.reset();
 }
 
+
 void HCSR04::rise (void (*fptr)(void))
 {
     echo.rise(fptr);
@@ -63,36 +87,15 @@
     echo.fall(fptr);
 }
 
+
 unsigned int HCSR04::get_dist_cm()
 {
     return distance;
 }
-unsigned int HCSR04::get_pulse_us()
-{
-    return pulsedur;
-}
-
 
 
-/*******************************************************
-   Here is a sample code usage
-********************************************************* 
-#include "hcsr04.h"
-HCSR04  usensor(p25,p6);
-int main()
-{
-    unsigned char count=0;
-    while(1) {
-        usensor.start();
-        wait_ms(500); 
-        dist=usensor.get_dist_cm();
-        lcd.cls();
-        lcd.locate(0,0);
-        lcd.printf("cm:%ld",dist );
- 
-        count++;
-        lcd.locate(0,1);
-        lcd.printf("Distance =%d",count);
-        
-    }
-*/
\ No newline at end of file
+void HCSR04::setTemp(int temp){
+    temperature = temp;
+    sonic = 331.5+0.61*temperature;
+    maxTime = 10*1000000/sonic;
+}
\ No newline at end of file

--- a/hcsr04.h	Sat Mar 30 18:55:03 2013 +0000
+++ b/hcsr04.h	Sat Sep 22 11:00:29 2018 +0000
@@ -53,16 +53,19 @@
     void isr_fall(void);
     void fall (void (*fptr)(void));
     void rise (void (*fptr)(void));
-
-
+    
+    void setTemp(int temp);
 
 private:
 
     Timer pulsetime;
+    float pulsetime_us;
+    unsigned int distance;
+    int temperature;
+    double maxTime;
+    double sonic;
     DigitalOut  trigger;
     InterruptIn echo;
-    unsigned int pulsedur;
-    unsigned int distance;
 };
 
 #endif
\ No newline at end of file