diff --git a/src/app_cfg.h b/src/app_cfg.h
index 36076ca..b18087f 100644
--- a/src/app_cfg.h
+++ b/src/app_cfg.h
@@ -77,7 +77,7 @@ extern "C" {
 	#define FLASH_CAP_SIZE_1M			1
 #endif
 	#define BOARD						BOARD_8258_03MMC//BOARD_8258_DONGLE//BOARD_8258_EVK
-	#define CLOCK_SYS_CLOCK_HZ  		48000000
+	#define CLOCK_SYS_CLOCK_HZ  		24000000 //48000000
 #elif defined(MCU_CORE_8278)
 	#define FLASH_CAP_SIZE_1M			1
 	#define BOARD						BOARD_8278_DONGLE//BOARD_8278_EVK