View Source HTS221.Server (hts221 v1.1.0)
Server for setting up and using the HTS221
When controlling the HTS221 there are few setup steps and other checks you may want to do. Also, to keep the transport layer working often times this will call for a GenServer. This server is meant to provide common functionality around setup and an expose a higher level API for application use.
This process can be added to your supervision tree.
def MyApp do
use Application
def start(_type, _args) do
children = [
... children ...
{HTS221.Server, transport: {HTS221.Transport.I2C, [bus_name: "i2c-1"]}
... children ...
]
opts = [strategy: :one_for_one, name: MyApp.Supervisor]
Supervisor.start(children, opts)
end
endIf you a custom transport implementation then the :transport argument to
this server will look different.
If the HTS221 is not detected this server will log that it was not found and
return :ignore on the GenServer.init/1 callback. This is useful if your FW
will run on devices with different hardware attached and don't want the device
availability to crash your application supervisor.
Link to this section Summary
Functions
Returns a specification to start this module under a supervisor.
Read the humidity level
Read the temperature value
Get the transport the server is using
Link to this section Types
Specs
arg() ::
{:transport,
HTS221.Transport.impl() | {HTS221.Transport.impl(), [HTS221.Transport.arg()]}}
| {:name, name()}
Arguments to the HTS221.Server
:transport- the transport implementation module and optional arguments:name- this is a named GenServer that either uses what you pass in orHTS221.Server
Specs
name() :: any()
Specs
temperature_opt() :: {:scale, HTS221.scale()}
Link to this section Functions
Returns a specification to start this module under a supervisor.
See Supervisor.
Specs
Read the humidity level
This is measured in percent.
Specs
start_link([arg()]) :: GenServer.on_start()
Specs
temperature(name(), [temperature_opt()]) :: {:ok, float()} | {:error, any()}
Read the temperature value
By default this is read in celsius you can the :scale option to change the
unit the temperature is measured in. See HTS221.scale() for more
information.
Specs
transport(name()) :: HTS221.Transport.t()
Get the transport the server is using
This is useful if you need to debug the registers using the functions in
HTS221 module.