diff --git a/bsp/stm32f20x/Libraries/CMSIS/CM3/DeviceSupport/ST/STM32F2xx/system_stm32f2xx.c b/bsp/stm32f20x/Libraries/CMSIS/CM3/DeviceSupport/ST/STM32F2xx/system_stm32f2xx.c
index da0e189c88126e1dfc85bdc518608ca10e24f789..63938af7353bb3ea1268d9be5ec6b46be968ff3e 100644
--- a/bsp/stm32f20x/Libraries/CMSIS/CM3/DeviceSupport/ST/STM32F2xx/system_stm32f2xx.c
+++ b/bsp/stm32f20x/Libraries/CMSIS/CM3/DeviceSupport/ST/STM32F2xx/system_stm32f2xx.c
@@ -142,7 +142,7 @@
 
 
 /* PLL_VCO = (HSE_VALUE or HSI_VALUE / PLL_M) * PLL_N */
-#define PLL_M      25
+#define PLL_M      (HSE_VALUE / 1000000)
 #define PLL_N      240
 
 /* SYSCLK = PLL_VCO / PLL_P */
diff --git a/bsp/stm32f40x/Libraries/CMSIS/ST/STM32F4xx/Source/Templates/system_stm32f4xx.c b/bsp/stm32f40x/Libraries/CMSIS/ST/STM32F4xx/Source/Templates/system_stm32f4xx.c
index 98e8e04dbe2a5c063e3ee92432db888af7fd37ba..18fa12b8038ee4733ca872a6e9d5d78d2581fabb 100644
--- a/bsp/stm32f40x/Libraries/CMSIS/ST/STM32F4xx/Source/Templates/system_stm32f4xx.c
+++ b/bsp/stm32f40x/Libraries/CMSIS/ST/STM32F4xx/Source/Templates/system_stm32f4xx.c
@@ -146,7 +146,7 @@
 
 /************************* PLL Parameters *************************************/
 /* PLL_VCO = (HSE_VALUE or HSI_VALUE / PLL_M) * PLL_N */
-#define PLL_M      25
+#define PLL_M      (HSE_VALUE / 1000000)
 #define PLL_N      336
 
 /* SYSCLK = PLL_VCO / PLL_P */