diff --git a/src/button.h b/src/button.h
index 69ec53c..352354a 100644
--- a/src/button.h
+++ b/src/button.h
@@ -11,7 +11,7 @@
 
 #include <stdint.h>
 
-extern uint32_t BUTTON_CYCLE;
+extern const uint32_t BUTTON_CYCLE;
 
 typedef enum {
   BUTTONS_FIRST,
diff --git a/src/eggTimer.h b/src/eggTimer.h
index 21274f2..3195e4b 100644
--- a/src/eggTimer.h
+++ b/src/eggTimer.h
@@ -11,6 +11,9 @@
 
 #include <stdint.h>
 
+extern const uint32_t EGG_TIMER_CYCLE;
+
+
 
 void eggTimerInit(void *handleArg);
 void eggTimerExec(void *handleArg);
diff --git a/src/main.c b/src/main.c
index 0adac1c..23af023 100644
--- a/src/main.c
+++ b/src/main.c
@@ -17,6 +17,7 @@
 #include "PontCoopScheduler.h"
 #include "measure.h"
 #include "eggTimer.h"
+#include "button.h"
 
 
 
@@ -42,11 +43,13 @@ int main() {
   measureInit(NULL);
   displayMuxerInit(NULL);
   eggTimerInit(NULL);
+  buttonInit(NULL);
 
   // schAdd(displayExec, NULL, 0, DISPLAY_CYCLE);
   schAdd(measureStartConversion, NULL, 0, MEASURE_CYCLE);
   schAdd(displayMuxerExec, NULL, 0, DISPLAY_MUXER_CYCLE);
   schAdd(eggTimerExec, NULL, 0, EGG_TIMER_CYCLE);
+  schAdd(buttonExec, NULL, 0, BUTTON_CYCLE);
 
   __enable_interrupt();