View Source Cantastic.Emitter (Cantastic v1.0.1)

Cantastic.Emitter is a GenServer used to emit CAN frames at the frequency defined in your YAML configuration file.

There is one Emitter process started per emitted frame on a CAN network.

Here is an example on how to configure a simple emitter and start emitting frames immediately:

  :ok = Emitter.configure(:network_name, "my_frame", %{
    parameters_builder_function: :default,
    initial_data: %{
      "gear" => "drive"
    },
    enable: true
  })

Summary

Functions

child_spec(init_arg)

Returns a specification to start this module under a supervisor.

configure(network_name, frame_name, initialization_args)

Configure the emitter, it has to be called before enable/2.

disable(network_name, frame_names)

Disable the emitter(s), the frame is/are then not emitted on the bus anymore.

enable(network_name, frame_names)

Enable the emitter(s), the frame(s) is/are then emitted on the bus at the predefined frequency.

forward(network_name, frame)

Forward a frame to another CAN network

get(emitter, fun, timeout \\ 5000)

send_frame(network_name, frame_name)

Send the frame once. configure/2 has to be called before the emitter can start emitting on the bus.

start_link(args)

update(network_name, frame_name, fun, timeout \\ 5000)

Update the emitter's data.

Functions

child_spec(init_arg)

Returns a specification to start this module under a supervisor.

See Supervisor.

configure(network_name, frame_name, initialization_args)

Configure the emitter, it has to be called before enable/2.

You must provide a parameters_builder_function that will be used by the emitter to compute the actual Cantastic.Signal value(s).

The function will receive the Emitter's data as a parameter and should return {:ok, parameters, data}, where parameters is a map containing a value for each signal of the emitter's frame.

If all you need is to send the current values stored in data, you can simply pass :default as parameters_builder_function, which is equivalent to fn (data) -> {:ok, data, data}.

You can start to emit immediately by setting the enable key to true.

The initial_data key allows you to provide the initial values.

Returns: :ok

Examples

iex> Cantastic.Emitter.configure(:network_name, %{
  parameters_builder_function: fn (data) ->
    {
      :ok,
      %{"counter" => data["counter"], "gear" => data["gear"]},
      %{data | "counter" => data["counter"] + 1}
    }
  end,
  initial_data: %{"counter" => 0, "gear" => "drive"}
})
:ok

iex> Cantastic.Emitter.configure(:network_name, %{
  parameters_builder_function: :default,
  initial_data: %{"gear" => "drive"},
  enable: true
})
:ok

disable(network_name, frame_names)

Disable the emitter(s), the frame is/are then not emitted on the bus anymore.

Returns: :ok

Examples

iex> Cantastic.Emitter.disable(:drive_can, "engine_status")
:ok

iex> Cantastic.Emitter.disable(:drive_can, ["engine_status", "throttle"])
:ok

enable(network_name, frame_names)

Enable the emitter(s), the frame(s) is/are then emitted on the bus at the predefined frequency.

Returns: :ok

Examples

iex> Cantastic.Emitter.enable(:drive_can, "engine_status")
:ok

iex> Cantastic.Emitter.enable(:drive_can, ["engine_status", "throttle"])
:ok

forward(network_name, frame)

Forward a frame to another CAN network

Returns: :ok

Examples

iex> Cantastic.Emitter.forward(:my_network, frame)
:ok

get(emitter, fun, timeout \\ 5000)

send_frame(network_name, frame_name)

Send the frame once. configure/2 has to be called before the emitter can start emitting on the bus.

Returns :ok.

Example

iex> Cantastic.Emitter.send_frame(:network_name, "my_frame")
:ok

start_link(args)

update(network_name, frame_name, fun, timeout \\ 5000)

Update the emitter's data.

It allows you to modify the signal's values to sent on the bus. Your function receives the data map and must return the updated version.

Returns: :ok

Examples

iex> Cantastic.Emitter.update(:network_name, "my_frame", fn(data) ->
  %{data | gear: "parking"}
end)
:ok