elixir_bme680

v0.1.0

elixir_bme680 v0.1.0 Bme680 View Source

elixir_bme680 provides a high level abstraction to interface with the BME680 environmental sensor on Linux platforms.

Link to this section Summary

Functions

child_spec(arg)

Returns a specification to start this module under a supervisor

init(list)

Invoked when the server is started. start_link/3 or start/3 will block until it returns

measure(pid)

Perform a measurement on the BME680 sensor and synchronously return it

measure_async(pid, send_to)

Perform a measurement on the BME680 sensor and asynchronously get the result as a message

start_link(bme_opts \\ [], opts \\ [])

Starts and links the Bme680 GenServer

stop(pid)

Gracefully stops the Bme680 GenServer

Link to this section Functions

Link to this function child_spec(arg) View Source

Returns a specification to start this module under a supervisor.

See Supervisor.

Link to this function init(list) View Source

Invoked when the server is started. start_link/3 or start/3 will block until it returns.

args is the argument term (second argument) passed to start_link/3.

Returning {:ok, state} will cause start_link/3 to return {:ok, pid} and the process to enter its loop.

Returning {:ok, state, timeout} is similar to {:ok, state} except handle_info(:timeout, state) will be called after timeout milliseconds if no messages are received within the timeout.

Returning {:ok, state, :hibernate} is similar to {:ok, state} except the process is hibernated before entering the loop. See c:handle_call/3 for more information on hibernation.

Returning {:ok, state, {:continue, continue}} is similar to {:ok, state} except that immediately after entering the loop the c:handle_continue/2 callback will be invoked with the value continue as first argument.

Returning :ignore will cause start_link/3 to return :ignore and the process will exit normally without entering the loop or calling c:terminate/2. If used when part of a supervision tree the parent supervisor will not fail to start nor immediately try to restart the GenServer. The remainder of the supervision tree will be started and so the GenServer should not be required by other processes. It can be started later with Supervisor.restart_child/2 as the child specification is saved in the parent supervisor. The main use cases for this are:

  • The GenServer is disabled by configuration but might be enabled later.
  • An error occurred and it will be handled by a different mechanism than the Supervisor. Likely this approach involves calling Supervisor.restart_child/2 after a delay to attempt a restart.

Returning {:stop, reason} will cause start_link/3 to return {:error, reason} and the process to exit with reason reason without entering the loop or calling c:terminate/2.

Callback implementation for GenServer.init/1.

Link to this function measure(pid) View Source 
measure(GenServer.server()) :: %Bme680.Measurement{
  gas_resistance: integer() | nil,
  humidity: float(),
  pressure: float(),
  temperature: float()
}

Perform a measurement on the BME680 sensor and synchronously return it

Link to this function measure_async(pid, send_to) View Source 
measure_async(GenServer.server(), pid()) :: :ok

Perform a measurement on the BME680 sensor and asynchronously get the result as a message

Link to this function start_link(bme_opts \\ [], opts \\ []) View Source 
start_link([i2c_device_number: integer(), i2c_address: 118 | 119], [term()]) ::
  GenServer.on_start()

Starts and links the Bme680 GenServer.

Link to this function stop(pid) View Source 
stop(GenServer.server()) :: :ok

Gracefully stops the Bme680 GenServer.