Peripheral Class Pattern

The Peripheral Class Pattern builds on the Base Class Pattern to provide a foundation for implementing access to different kinds of peripheral devices.

Constructor

Peripheral()

Creates a new Peripheral object instance.

Peripheral(options)

Parameters

options

An object of properties used to construct the class. The options object defines the hardware connections of the peripheral. These use the same properties as the IO types corresponding to the peripheral. The following are defined by this abstract class:

io: the constructor for the IO Class used to communicate with the peripheral

The rest of the options should include the properties accepted by the io constructor. See the example for more details.

If the peripheral has multiple hardware connections, the options object will accept seperate top-level properties to nest the options for each io type, see examples for more detauls.

Instance Properties

Classes that conform to this class pattern may choose to provide accessors, e.g. setters and getters, for configuration properties.

A setter should behave in the same way as the configure method invoked with a single property.

Instance Methods

close

Releases all resources associated with the instance before completing. It may be called more than once without erroring. Once this method has been called, calling other methods on the instance throws an exception.

close()

configure

Modifies how the peripheral operates. A given call to this method should only modify the features specified in the options object. It may be called more than once.

configure(options)

Parameters

options

Follows the same rules as the options used in the constructor.

Examples

This is an abstract class that is not instantiated directly. The examples that follow are demonstrations of potential implementations.

The following code is an example of using an I²C peripheral:

import I2CPeripherial from "embedded:example/i2cperipherial";
import I2C from "embedded:io/i2c";

const periph = new I2CPeripherial({
    io: I2C,
    data: 4,
    clock: 5,
    address: 0x30,
});

The following code is an example of a peripheral that has multiple hardware connections:

import I2CPeripheralWithInterrupt from "embedded:example/i2cperipheralwithinterrupt";
import I2C from "embedded:io/i2c";
import Digital from "embedded:io/digital";

const periph = new I2CPeripheralWithInterrupt({
    communication: {
        io: I2C,
        data: 4,
        clock: 5,
        address: 0x30
    },
    interrupt: {
        io: Digital,
        pin: 5
    }
});

Specifications

Peripheral Class Pattern