Overview

One of the main steps in realizing a cellular IoT application is, naturally, obtaining an LTE connection. In this lesson, we will cover two different methods an application can use to obtain a cellular connection. First, we will look at AT commands over serial communication, both standard and proprietary. We will go through the syntax and some of the most commonly used commands. Then we will take a look at the LTE link controller library in the nRF Connect SDK, and how you can use it to initialize an LTE connection.

In the exercise section of this lesson, you will first learn how to initialize and configure the modem and then establish an LTE connection (LTE-M or NB-IoT) using AT commands. Then you’ll learn how to use the LTE link controller library to asynchronously perform the same setup, and how to enable unsolicited AT command notifications in your application.

Objectives

• Understand the use and syntax of the AT command interface and the most common AT commands.
• Examine the LTE link controller library and use cases, and understand the underlying AT commands.
• Practice through hands-on exercises how to:
  • Use the AT command interface to configure and initialize the modem, and establish an LTE connection.
  • Use the LTE link controller library to asynchronously establish an LTE connection.