Book Image

DIY Microcontroller Projects for Hobbyists

By : Miguel Angel Garcia-Ruiz, Pedro Cesar Santana Mancilla
Book Image

DIY Microcontroller Projects for Hobbyists

By: Miguel Angel Garcia-Ruiz, Pedro Cesar Santana Mancilla

Overview of this book

We live in a world surrounded by electronic devices, and microcontrollers are the brains of these devices. Microcontroller programming is an essential skill in the era of the Internet of Things (IoT), and this book helps you to get up to speed with it by working through projects for designing and developing embedded apps with microcontroller boards. DIY Microcontroller Projects for Hobbyists are filled with microcontroller programming C and C++ language constructs. You'll discover how to use the Blue Pill (containing a type of STM32 microcontroller) and Curiosity Nano (containing a type of PIC microcontroller) boards for executing your projects as PIC is a beginner-level board and STM-32 is an ARM Cortex-based board. Later, you'll explore the fundamentals of digital electronics and microcontroller board programming. The book uses examples such as measuring humidity and temperature in an environment to help you gain hands-on project experience. You'll build on your knowledge as you create IoT projects by applying more complex sensors. Finally, you'll find out how to plan for a microcontroller-based project and troubleshoot it. By the end of this book, you'll have developed a firm foundation in electronics and practical PIC and STM32 microcontroller programming and interfacing, adding valuable skills to your professional portfolio.
Table of Contents (16 chapters)

Testing the system

In this last section of the chapter, we will connect an 8x8 LED matrix to display an alert if the sensor detects the presence of gas in the environment.

An LED matrix is a set of LEDs grouped into rows and columns. By turning on these LEDs, you can create graphics or text, which are widely used for billboards and traffic signs.

There is an electronic component for small-scale projects called an 8x8 LED matrix. It is composed of 64 LEDs arranged in eight rows and eight columns (see Figure 8.14):

Figure 8.14 – LED matrix 8x8

Figure 8.14 – LED matrix 8x8

As you can see in the previous figure, the 8x8 LED matrix has pins to control the rows and columns, so it is impossible to control each LED independently.

This limitation implies having to use 16 digital signals and refreshes the image or text continuously. Therefore, the integrated MAX7219 and MAX7221 circuits have been created to facilitate this task; the circuits are almost identical and interchangeable...