diff --git a/firmware/applications/tester.c b/firmware/applications/tester.c
index 667b335..d494e42 100644
--- a/firmware/applications/tester.c
+++ b/firmware/applications/tester.c
@@ -16,3 +16,5 @@ void main_tester(void) {
     handleMenu(&mainmenu);
     gotoISP();
 };
+
+void tick_tester(void);