diff --git a/sysmoOCTSIM/gcc/system_same54.c b/sysmoOCTSIM/gcc/system_same54.c
index 55a5fd2..9d17c8d 100644
--- a/sysmoOCTSIM/gcc/system_same54.c
+++ b/sysmoOCTSIM/gcc/system_same54.c
@@ -28,12 +28,13 @@
  */
 
 #include "same54.h"
+#include "peripheral_clk_config.h"
 
 /**
  * Initial system clock frequency. The System RC Oscillator (RCSYS) provides
  *  the source for the main clock at chip startup.
  */
-#define __SYSTEM_CLOCK (48000000)
+#define __SYSTEM_CLOCK CONF_CPU_FREQUENCY
 
 uint32_t SystemCoreClock = __SYSTEM_CLOCK; /*!< System Clock Frequency (Core Clock)*/