diff --git a/Makefile b/Makefile
--- a/Makefile
+++ b/Makefile
@@ -96,6 +96,7 @@ OBJCOPY=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PR
 AS=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-as
 AR=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-ar
 GDB=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-gdb
+SIZE=$(TOOLCHAIN_PATH)/$(TOOLCHAIN_PREFIX)-size
 
 
 all: $(OBJ)
@@ -110,3 +111,9 @@ clean:
 	rm -f $(TARGET).elf
 	rm -f $(TARGET).hex
 	rm -f $(TARGET).bin
+
+# Display size
+size: $(TARGET).elf
+	@echo Invoking: ARM GNU Print Size
+	$(SIZE) --format=berkeley $<
+	@echo
diff --git a/main.c b/main.c
--- a/main.c
+++ b/main.c
@@ -6,6 +6,54 @@ static __IO uint32_t TimingDelay;
 uint8_t BlinkSpeed = 0;
 
 
+ErrorStatus HSEStartUpStatus;
+// Clock config
+void RCC_Configuration(void)
+{   
+  /* RCC system reset(for debug purpose) */
+  RCC_DeInit();
+
+  /* Enable HSE */
+  RCC_HSEConfig(RCC_HSE_ON);
+
+  /* Wait till HSE is ready */
+  HSEStartUpStatus = RCC_WaitForHSEStartUp();
+
+  if(HSEStartUpStatus == SUCCESS)
+  {
+    /* HCLK = SYSCLK */
+    RCC_HCLKConfig(RCC_SYSCLK_Div1); 
+  
+    /* PCLK2 = HCLK */
+    RCC_PCLK2Config(RCC_HCLK_Div1); 
+
+    /* PCLK1 = HCLK/2 */
+    RCC_PCLK1Config(RCC_HCLK_Div2);
+
+    /* PLLCLK = 8MHz * 8 = ?? MHz */
+    RCC_PLLConfig(RCC_PLLSource_HSE, RCC_PLLMul_8, RCC_PLLDiv_2);
+
+    /* Enable PLL */ 
+    RCC_PLLCmd(ENABLE);
+
+    /* Wait till PLL is ready */
+    while(RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET)
+    {
+    }
+
+    /* Select PLL as system clock source */
+    RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
+
+    /* Wait till PLL is used as system clock source */
+    while(RCC_GetSYSCLKSource() != 0x08)
+    {
+    }
+  }
+
+  /* Enable GPIO_LED clock */
+//  RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIO_LED, ENABLE);
+}
+
 /* Main */
 int main(void)
 {
@@ -16,6 +64,7 @@ int main(void)
   STM_EVAL_LEDInit(LED4);
   
 
+//  RCC_Configuration();
   /* Initialize User_Button on STM32L100C-Discovery */
   //STM_EVAL_PBInit(BUTTON_USER, BUTTON_MODE_GPIO);
   
@@ -26,6 +75,10 @@ int main(void)
  /* Initiate Blink Speed variable */ 
   BlinkSpeed = 1;
 
+  while(1) {
+	  ITM_SendChar('!');
+  } 
+
  /* Init lcd driver */
   SSD1303_Init();
   SSD1303_DrawPoint(3,3,1);