Book Image

Hands-On Internet of Things with MQTT

By : Tim Pulver
Book Image

Hands-On Internet of Things with MQTT

By: Tim Pulver

Overview of this book

MQ Telemetry Transport (MQTT) is a lightweight messaging protocol for smart devices that can be used to build exciting, highly scalable Internet of Things (IoT) projects. This book will get you started with a quick introduction to the concepts of IoT and MQTT and explain how the latter can help you build your own internet-connected prototypes. As you advance, you’ll gain insights into how microcontrollers communicate, and you'll get to grips with the different messaging protocols and techniques involved. Once you are well-versed with the essential concepts, you’ll be able to put what you’ve learned into practice by building three projects from scratch, including an automatic pet food dispenser and a smart e-ink to-do display. You’ll also discover how to present your own prototypes professionally. In addition to this, you'll learn how to use technologies from third-party web service providers, along with other rapid prototyping technologies, such as laser cutting, 3D printing, and PCB production. By the end of this book, you’ll have gained hands-on experience in using MQTT to build your own IoT prototypes.
Table of Contents (16 chapters)
Title Page

Making your e-paper device accessible via serial

The next thing we want to do is make the text on the screen dynamic by adding serial communication. At the beginning, the text was static and defined as the HelloWorld variable. Now we have changed it to be a dynamic parameter of our setText function, but the way we use it is still static, because we just pass the "Hello display" static text to it via setText("Hello display");.

To make use of the serial port, let's find an example first that reads in a string from the serial port. We will then integrate it into our sketch. All the serial port examples can be found under File | Examples | 04.Communication.

Sadly, there is none that receives an input string and then does something with it.

We can have a look at the Arduino serial reference (https://www.arduino.cc/reference/en/language/functions...