From 42f9726b6fb134b61816470b0cb5172020030fae Mon Sep 17 00:00:00 2001
From: Toumal <toumaltheorca@gmail.com>
Date: Fri, 13 Sep 2013 21:11:55 +0200
Subject: [PATCH] Added interrupt handling and speaker output for radiation
 detection clicks

---
 RadiationWatch.cpp | 28 +++++++++++++++-------------
 RadiationWatch.h   |  8 ++++----
 readme.md          |  8 +++++++-
 3 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/RadiationWatch.cpp b/RadiationWatch.cpp
index 7682aa5..fd3b2fe 100644
--- a/RadiationWatch.cpp
+++ b/RadiationWatch.cpp
@@ -6,12 +6,20 @@
 #include "Arduino.h"
 #include "RadiationWatch.h"
 
-RadiationWatch::RadiationWatch(int signPin, int noisePin) : _signPin(signPin), _noisePin(noisePin)
+int signCount;  //Counter for Radiation Pulse
+
+//Called via Interrupt when a radiation pulse is detected
+void triggerRadiationPulse() {
+  signCount++;
+  tone(8, 800, 1); // Output classic geiger counter tick noise
+}
+
+RadiationWatch::RadiationWatch(int signPin, int noisePin, int signIRQ) : _signPin(signPin), _noisePin(noisePin), _signIRQ(signIRQ)
 {
+  signCount = 0;
   _prevTime = 0;
   index = 0;
   
-  signCount = 0;
   noiseCount = 0;
   
   sON = 0;
@@ -38,6 +46,10 @@ void RadiationWatch::setup()
   pinMode(_noisePin,INPUT);
   digitalWrite(_noisePin,HIGH);
   
+  //Attach interrupt handler to catch incoming radiation pulses, 
+  //and execute triggerRadiationPulse() when this happens.
+  attachInterrupt(_signIRQ, triggerRadiationPulse, FALLING);
+
   //Initialize cpmHistory[]
   for(int i = 0; i < kHistoryCount;i++ )
   {
@@ -61,19 +73,9 @@ void RadiationWatch::loop()
 {
   // Raw data of Radiation Pulse: Not-detected -> High, Detected -> Low
   int sign = signPin();
-
   // Raw data of Noise Pulse: Not-detected -> Low, Detected -> High
   int noise = noisePin();
 
-  //Radiation Pulse normally keeps low for about 100[usec]
-  if(sign==0 && sON==0)
-  {//Deactivate Radiation Pulse counting for a while
-    sON = 1;
-    signCount++;
-  }else if(sign==1 && sON==1){
-    sON = 0;
-  }
-
   //Noise Pulse normally keeps high for about 100[usec]
   if(noise==1 && nON==0)
   {//Deactivate Noise Pulse counting for a while
@@ -203,7 +205,7 @@ double RadiationWatch::uSvhError()
   }
 }
 
-RadiationWatchPrinter::RadiationWatchPrinter(int signPin, int noisePin) : RadiationWatch(signPin, noisePin)
+RadiationWatchPrinter::RadiationWatchPrinter(int signPin, int noisePin, int signIRQ) : RadiationWatch(signPin, noisePin, signIRQ)
 {
 }
 
diff --git a/RadiationWatch.h b/RadiationWatch.h
index 049d551..c9a27eb 100644
--- a/RadiationWatch.h
+++ b/RadiationWatch.h
@@ -11,7 +11,7 @@
 class RadiationWatch
 {
   public:
-    RadiationWatch(int signPin, int noisePin);
+    RadiationWatch(int signPin, int noisePin, int signIRQ);
     
     void setup();
     void loop();
@@ -31,7 +31,7 @@ class RadiationWatch
     
     double cpmTime();
   
-    static const unsigned int kHistoryCount = 200;
+    static const unsigned int kHistoryCount = 50; // was 200
 
     double _cpmHistory[kHistoryCount]; //History of count rates
     
@@ -39,10 +39,10 @@ class RadiationWatch
 
     int _signPin;   //Radiation Pulse (Yellow)
     int _noisePin;  //Vibration Noise Pulse (White)
+	int _signIRQ;	//The IRQ number for the radiation pulse pin (depends on Arduino model)
 
     int index; //Number of loops
     
-    int signCount;  //Counter for Radiation Pulse
     int noiseCount;  //Counter for Noise Pulse
     
     int sON;//Lock flag for Radiation Pulse
@@ -63,7 +63,7 @@ class RadiationWatch
 class RadiationWatchPrinter : public RadiationWatch
 {
   public:
-    RadiationWatchPrinter(int signPin, int noisePin);
+    RadiationWatchPrinter(int signPin, int noisePin, int signIRQ);
   
     virtual void printKey();
     virtual void printStatus();
diff --git a/readme.md b/readme.md
index f0aa60e..165aebe 100644
--- a/readme.md
+++ b/readme.md
@@ -2,4 +2,10 @@
 
 An Arduino library to interface with the [Radiation Watch](http://www.radiation-watch.org/) Pocket Geiger
 
-Based on the [Radiation Watch sample code](http://radiation-watch.sakuraweb.com/share/ARDUINO.zip).
+Based on [thomasaw's library](https://github.com/thomasaw/RadiationWatch) and the [Radiation Watch sample code](http://radiation-watch.sakuraweb.com/share/ARDUINO.zip)
+
+Changes in this version:
+
+x) Changed from using loops for the radiation detection to interrupts
+
+x) Added support for classic radiation "click" via speaker