for (;;)\r
{\r
/* Echo bytes from the host to the target via the hardware USART */\r
- if (CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface))\r
+ if (CDC_Device_BytesReceived(&VirtualSerial_CDC_Interface) > 0)\r
{\r
Serial_TxByte(CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface));\r
\r