diff --git a/cores/arduino/trap_handler.c b/cores/arduino/trap_handler.c
index f302625..99a1172 100644
--- a/cores/arduino/trap_handler.c
+++ b/cores/arduino/trap_handler.c
@@ -19,7 +19,7 @@ void __attribute__((weak)) ISR(void)
     /* 
     A dummy function for the case when additional interrupts are not used in the project.
     In the project, you need to create a function of the form:
-    extern "C" void ISR(void)
+    extern "C" void ISR()
     {
         // timer16 is taken as an example
         if (TIM16_GET_ARRM_INT_STATUS(htimer16_1_))