Generic sensor services

This package provides a set of generic sensor services that can be used to abstract the underlying sensor implementation. Drivers implement these services, so that their functionality can be accessed through Toit's RPC mechanism.

Clients

Clients import this sensor package and then call the service's client method to get a client object that implements that interface (assuming a provider is installed).

import sensors.temperature

main:
  // Some sensors might have multiple versions of the same service.
  // Each version has a getter to create the corresponding client.
  client := temperature.v1
  print client.read

Providers

Drivers provide the corresponding providers. They implement sensor-specific interfaces (like TemperatureSensor-v1). Each interface is versioned, so that the package can evolve in the future.

Drivers can implement multiple interfaces. For example, the BME280 driver implements the TemperatureSensor and HumiditySensor interfaces.

Example

The following example demonstrates how to implement a provider for the TemperatureSensor-v1 interface.

import sensors.providers

class TemperatureSensor implements providers.TemperatureSensor-v1:
  // API functions are always prefixed with the sensor's category, so that
  // drivers can implement multiple interfaces without name clashes.
  temperature-read -> float:
    return 25.0

  close:
    // Do nothing in this example.

install:
  provider := providers.Provider "toit.io/sensors/temperature"
      --major=1
      --minor=0
      --open=:: TemperatureSensor  // Create a new instance.
      --close=:: it.close
      --handlers=[providers.TemperatureHandler-v1]
  handler.install