diff --git a/f8/timer.h b/f8/timer.h
index e3e0b61..71a1db0 100644
--- a/f8/timer.h
+++ b/f8/timer.h
@@ -9,6 +9,7 @@ namespace f8
     {
     public:
         TimerWp(a8::XTimerWp wp): p_(wp) {};
+        TimerWp() {};
         bool expired() { return p_.expired();};
         auto lock() { return p_.lock(); };