优化PIBot的驱动，解决串口打印导致死机问题

Hardware/Pibot驱动底盘/PiRobot_Firmware v1.0/STM32/User/stm32f10x_it.cpp

@@ -160,6 +160,15 @@ void USART3_IRQHandler(void)
     }
 }
 
+void USART1_IRQHandler(void)
+{
+    if (USART_GetITStatus(USART1, USART_IT_RXNE) != RESET)
+    {
+        USART_ReceiveData(USART1);
+        USART_ClearITPendingBit(USART1,USART_IT_RXNE);  //clear interrupt flag
+    }
+}
+
 /******************************************************************************/
 /*                 STM32F10x Peripherals Interrupt Handlers                   */
 /*  Add here the Interrupt Handler for the used peripheral(s) (PPP), for the  */