Diff: FreqMesure.h

Revision:

20:00a9a95ef083

Child:

22:644d53f1f291

diff -r 304b17087d06 -r 00a9a95ef083 FreqMesure.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/FreqMesure.h	Tue Mar 04 18:42:38 2014 +0000
@@ -0,0 +1,55 @@
+/***************************************************************************************
+Measure the frequency of a 3.3v square wave signal once every second. The frequency range
+is 500Hz to 1000Hz with 50% duty cycle). In this code the on complet cycle is peiod is 
+masured after detcting the edge also a timeout timer is seting to detect open loop.
+*****************************************************************************************/
+
+void FreqMsur(){
+    FreqMsurPin = ! (FreqMsurPin);   //Pin 23
+    FreqTimeOut.start();
+    // Ignore first part of the signal to detect the edge
+    if(!FrequencyIn){ 
+        while(!FrequencyIn){
+            if (FreqTimeOut.read_ms() > 4)
+                break;
+        }
+    }
+    else{
+        while(FrequencyIn){
+            if (FreqTimeOut.read_ms() > 4)
+                break;
+        }
+    }
+    //This is the begining of the edge start the timer to masure
+    FreqMsurT.start();
+    if (FreqTimeOut.read_ms() > 4){
+           FreqTimeOutHpn=1;
+    }
+    else{
+            FreqTimeOutHpn=0;
+    }
+    FreqTimeOut.stop(); 
+    FreqTimeOut.reset();
+    if(!FreqTimeOutHpn){
+        if(!FrequencyIn){
+            while(!FrequencyIn){
+            }
+            while(FrequencyIn){
+            }
+        }
+        else{
+            while(FrequencyIn){
+            }
+            while(!FrequencyIn){
+            }
+        }    
+        FreqMsurT.stop();
+        float Period=FreqMsurT.read_us();
+        Freq=1/Period*1000000.0+0.5;  //Adding 0.5 to round the frequency to nearst int
+    }
+    else{
+        Freq=0xffff; 
+    }                
+    FreqTimeOut.stop();
+    FreqMsurT.reset();
+}