diff --git a/portable/GCC/ATmegaxxxx/port.c b/portable/GCC/ATmegaxxxx/port.c
index d65cfedc2..270319ce8 100644
--- a/portable/GCC/ATmegaxxxx/port.c
+++ b/portable/GCC/ATmegaxxxx/port.c
@@ -678,7 +678,7 @@ void vPortYieldFromTick( void )
     }
     portRESTORE_CONTEXT();
 
-    __asm__ __volatile__ ( "reti" );
+    __asm__ __volatile__ ( "ret" );
 }
 /*-----------------------------------------------------------*/
 
@@ -751,6 +751,7 @@ uint8_t ucLowByte;
     ISR(portSCHEDULER_ISR)
     {
         vPortYieldFromTick();
+        __asm__ __volatile__ ( "reti" );
     }
 #else