Overview

A device driver is a combination of statically allocated structures maintained in the kernel that contain information about the device instance. Some of the device information that is worth mentioning is config, data, state, and an API to access the device-specific implementation of all the features supported for this specific device.

In this lesson, we will cover the device driver model, API, instances and implementation. Then we will take a look at the sensor driver API available in nRF Connect SDK, and how to add a custom sensor to it.

In the exercise section, we will use the BME280 sensor with the SPI interface that was used in Lesson 5. We will practice creating a custom driver for this sensor using the sensor driver API.

Objectives

• Explore the available options for adding a custom device driver
• Understand the different application types in nRF Connect SDK
• Learn how to add a sensor to the Zephyr sensor driver API
• Practice through hands-on exercise setting up a west workspace and adding a custom device driver to the application

Prerequisites

Complete Lesson 5 before starting this lesson. We will use the same SPI instance with the same sensor (BME280) and dive deeper into the details of the underlying device driver.