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)

Introducing the MQ-2 gas sensor

In this section, we will get to know the details of the main hardware component to build our gas sensor: the MQ-2 sensor. This sensor is recommended to detect LPG, propane, alcohol, and smoke, mainly with concentrations between 300 and 10,000 parts per million (ppm). So, we can say that it is a sensor to detect smoke and flammable gases.

Concentration refers to the amount of gas in the air and is measured in ppm. That is, if you have 2,000 ppm of LPG, it means that in a million gas molecules, only 2,000 ppm would be LPG and 998,000 ppm other gases.

The MQ-2 gas sensor is an electrochemical sensor that varies its resistance when exposed to certain gasses. It includes a small heater to raise the circuit's internal temperature, which provides the necessary conditions for the detection of substances. With the 5 V connection on the pins, the sensor is kept warm enough to function correctly.

Important note

The sensor can get very hot, so it...