diff --git a/hw/bsp/samd21/family.c b/hw/bsp/samd21/family.c
index 3fa6ea7d8..cead582e9 100644
--- a/hw/bsp/samd21/family.c
+++ b/hw/bsp/samd21/family.c
@@ -75,7 +75,9 @@ void board_init(void)
   // Update SystemCoreClock since it is hard coded with asf4 and not correct
   // Init 1ms tick timer (samd SystemCoreClock may not correct)
   SystemCoreClock = CONF_CPU_FREQUENCY;
+#if CFG_TUSB_OS  == OPT_OS_NONE
   SysTick_Config(CONF_CPU_FREQUENCY / 1000);
+#endif
 
   // Led init
 #ifdef LED_PIN