Circuits.I2C.Backend behaviour (circuits_i2c v2.1.0)

View Source

Backends provide the connection to the real or virtual I2C controller

Summary

Types

transfer_options()

I2C transfer options

Callbacks

bus_names(options)

Return the I2C bus names on this system

info()

Return information about this backend

open(bus_name, options)

Open an I2C bus

Types

transfer_options()

@type transfer_options() :: keyword()

I2C transfer options

Support for options is backend-specific. Backends are encouraged to implement the following:

  • :retries - the number of retries for this transaction

Callbacks

bus_names(options)

@callback bus_names(options :: keyword()) :: [binary()]

Return the I2C bus names on this system

See backend documentation for options.

info()

@callback info() :: map()

Return information about this backend

open(bus_name, options)

@callback open(bus_name :: String.t(), options :: keyword()) ::
  {:ok, Circuits.I2C.Bus.t()} | {:error, term()}

Open an I2C bus

Bus names are typically of the form "i2c-n" and available buses may be found by calling bus_names/1.

See Circuits.I2C.open_options/0 for guidance on options.