diff --git a/libraries/MySensors/core/MyHwATMega328.cpp b/libraries/MySensors/core/MyHwATMega328.cpp
index 4e73b0a..5380d6a 100644
--- a/libraries/MySensors/core/MyHwATMega328.cpp
+++ b/libraries/MySensors/core/MyHwATMega328.cpp
@@ -21,7 +21,7 @@
 
 #include "MyHwATMega328.h"
 
-int8_t pinIntTrigger = 0;
+volatile int8_t pinIntTrigger = 0;
 
 void wakeUp()	 //place to send the interrupts
 {