A library for interfacing with a HP 7475a pen plotter Inspired by the great Georg Nees

See the sample dir for usage examples

On Linux you may need to add yourself to the dialout group to access devices in the /dev/tty* area. If nothing happens when you boot an iex shell, that means the plotter hasn't been initialized and you should check this.

To really make sure that's what it is, run this in iex (replacing "ttyUSB0" with your device)

iex> Circuits.UART.enumerate() # This will list your available devices
iex> {:ok, pid} = Circuits.UART.start_link()
iex> Circuits.UART.open(pid, "ttyUSB0", speed: 9600, active: true)

If that returns {:error, :eacces} then you need to be in dialout (also log out and back in)

If available in Hex, the package can be installed by adding nees to your list of dependencies in mix.exs:

def deps do
  [
    {:nees, "~> 0.1.0"}
  ]
end

Documentation can be generated with ExDoc and published on HexDocs. Once published, the docs can be found at https://hexdocs.pm/nees.