diff --git a/cores/arduino/startup.c b/cores/arduino/startup.c
index 1eda635b7b26c0f6137579409a4b7ad3f2d5c872..f5113227135957a9d532490279fdd385db2261ab 100644
--- a/cores/arduino/startup.c
+++ b/cores/arduino/startup.c
@@ -37,6 +37,8 @@ void Dummy_Handler(void);
 #if defined DEBUG
 void HardFault_Handler( void )
 {
+  __BKPT( 3 ) ;
+
   while ( 1 )
   {
   }
@@ -386,6 +388,10 @@ void Reset_Handler( void )
  */
 void Dummy_Handler( void )
 {
+#if defined DEBUG
+  __BKPT( 3 ) ;
+#endif // DEBUG
+
   while ( 1 )
   {
   }