diff --git a/User/system_ch32v00x.c b/User/system_ch32v00x.c
index ffaf4b8..cf962f0 100644
--- a/User/system_ch32v00x.c
+++ b/User/system_ch32v00x.c
@@ -17,10 +17,10 @@
 
 //#define SYSCLK_FREQ_8MHz_HSI    8000000
 //#define SYSCLK_FREQ_24MHZ_HSI   HSI_VALUE
-//#define SYSCLK_FREQ_48MHZ_HSI   48000000
+#define SYSCLK_FREQ_48MHZ_HSI   48000000
 //#define SYSCLK_FREQ_8MHz_HSE    8000000
 //#define SYSCLK_FREQ_24MHz_HSE   HSE_VALUE
-#define SYSCLK_FREQ_48MHz_HSE   48000000
+//#define SYSCLK_FREQ_48MHz_HSE   48000000
 
 /* Clock Definitions */
 #ifdef SYSCLK_FREQ_8MHz_HSI