diff --git a/bsp/lpc824/drivers/board.c b/bsp/lpc824/drivers/board.c
index 8ad077dbc6..ea941abc64 100644
--- a/bsp/lpc824/drivers/board.c
+++ b/bsp/lpc824/drivers/board.c
@@ -60,6 +60,7 @@ void SysTick_Handler(void)
  */
 void rt_hw_board_init()
 {
+    SystemCoreClockUpdate();
     SysTick_Config(SystemCoreClock / RT_TIMER_TICK_PER_SECOND);
 
 #ifdef RT_USING_COMPONENTS_INIT