   @doc """
   Write data to the opened UART with the default timeout.
   """
+  @spec write(pid, binary | [byte]) :: :ok | {:error, term}
   def write(pid, data) do
     write(pid, data, 5000)
   end

  @doc """
  Stop the UART GenServer.
  """
  def stop(pid) do
    GenServer.stop(pid)
  end

    * `:description` - A description or product name
    * `:serial_number` - The device's serial number if it has one
  """
  @spec enumerate() :: map
  def enumerate() do
    Nerves.UART.Enumerator.enumerate
  end
