diff --git a/window1/window1.ino b/window1/window1.ino
index 4658d54..73e53a5 100644
--- a/window1/window1.ino
+++ b/window1/window1.ino
@@ -9,7 +9,8 @@
 ContactSensor sensor = ContactSensor(WINDOW1, SENDER);
 
 volatile int counter = 0;
-bool currentState;
+volatile bool currentState;
+volatile bool shouldSend = true;
 
 void setup() {
     
@@ -19,27 +20,24 @@ void setup() {
 
   sensor.setup();
 
-  updateState();
-  sensor.sendStateAndVoltage(readState());
-
   TinyPower::setup();
   TinyPower::enableWdt(WDTO_8S);
 }
 
 void loop() {
+  if (shouldSend) {
+	  shouldSend = false;
+	  sensor.sendStateAndVoltage(readState());
+  }
   TinyPower::sleep();
 }
 
-void updateState() {
-  currentState = readState();
-}
-
 byte readState() {
   return digitalRead(SWITCH);
 }
 
 ISR(PCINT0_vect) {
-  sensor.sendStateAndVoltage(readState());
+  shouldSend = true;
   wdt_reset();
   counter = 0;
 }
@@ -47,13 +45,13 @@ ISR(PCINT0_vect) {
 ISR(WDT_vect) {
   bool state = readState();
   if (state != currentState) {
-	sensor.sendStateAndVoltage(state);
-	currentState = state;
-	return;
+	  shouldSend = true;
+	  currentState = state;
+	  return;
   }
   counter++;
   if (counter % 225 == 0) {
-	sensor.sendStateAndVoltage(readState());
-    counter = 0;
+	  shouldSend = true;
+	  counter = 0;
   }
 }
diff --git a/window2/window2.ino b/window2/window2.ino
index fb7e9dd..c1792d5 100644
--- a/window2/window2.ino
+++ b/window2/window2.ino
@@ -8,7 +8,8 @@
 ContactSensor sensor = ContactSensor(WINDOW2, SENDER);
 
 volatile int counter = 0;
-bool currentState;
+volatile bool currentState;
+volatile bool shouldSend = true;
 
 void setup() {
     
@@ -16,27 +17,24 @@ void setup() {
 
   sensor.setup();
 
-  updateState();
-  sensor.sendStateAndVoltage(readState());
-
   TinyPower::setup();
   TinyPower::enableWdt(WDTO_8S);
 }
 
 void loop() {
+  if (shouldSend) {
+	  shouldSend = false;
+	  sensor.sendStateAndVoltage(readState());
+  }
   TinyPower::sleep();
 }
 
-void updateState() {
-  currentState = readState();
-}
-
 byte readState() {
   return digitalRead(SWITCH);
 }
 
 ISR(PCINT0_vect) {
-  sensor.sendStateAndVoltage(readState());
+  shouldSend = true;
   wdt_reset();
   counter = 0;
 }
@@ -44,13 +42,13 @@ ISR(PCINT0_vect) {
 ISR(WDT_vect) {
   bool state = readState();
   if (state != currentState) {
-	sensor.sendStateAndVoltage(state);
-    currentState = state;
-    return;
+	  shouldSend = true;
+	  currentState = state;
+	  return;
   }
   counter++;
   if (counter % 225 == 0) {
-	sensor.sendStateAndVoltage(readState());
-    counter = 0;
+	  shouldSend = true;
+	  counter = 0;
   }
 }