void USART2_IRQHandler(void){

  extern char RxBuffer[];
  extern u8 RxCounter;
  extern u8 newline;
  extern u8 command_received;
  extern u8 PEMode;

  // receive UART2 int flag set
  if(USART_GetITStatus(USART2, USART_IT_RXNE) != RESET)
  {
    // Disable USART2 Receive interrupt
    USART_ITConfig(USART2, USART_IT_RXNE, DISABLE);



//    if(!PEMode) // L4LMode
//    {
      // Read one byte from the receive data register
      RxBuffer[RxCounter] = (USART_ReceiveData(USART2));
      // echo character
      USART_SendData(USART2,  RxBuffer[RxCounter]);
      // check for <LF> or <CR> and insert null terminator
      if((RxBuffer[RxCounter] == 0X0A) || (RxBuffer[RxCounter]) == 0X0D)
      {
        RxBuffer[RxCounter] = 0X00;
        RxCounter = 0;
        command_received=TRUE;  // command received and needs parsing
      }
      else
      {
        if(RxBuffer[RxCounter] == 0X08)
          { // backspace detected, decrement counter
           if(RxCounter > 0) RxCounter--;
        }
       else
        {
          RxCounter++;
        }
      }
    //}

  /*

   // PE MODE
    else
    { // PEMode
      //cmd_buf[byte_ptr] = S1BUF;
      // Read one byte from the receive data register
      RxBuffer[RxCounter] = (USART_ReceiveData(USART2));
      if(RxBuffer[0] == 0X05) RxCounter++;
      if(RxCounter >= 5)
      {
        RxCounter = 0;
        command_received = TRUE;
      }
    }*/

  }
  // re-enable USART2 Receive Interrupt
  USART_ITConfig(USART2, USART_IT_RXNE, ENABLE);
}