- PWM stands for Pulse-width modulation, it sets the percentage of time that a pin is HIGH and LOW. For an LED, it sets the effective brightness.
- The Raspberry Pi 3 B+ has 2 PWM pins, but they operate on the same channel, effectively creating 1 PWM pin.
- We need the GPIO expander because the RGB LED needs 3 PWM pins to fully function, and the Pi only has 1 on board.
- 7 -- red, green, blue, white (red+green+blue), yellow (red+green), purple (red+blue), and cyan (green+blue).
- The GPIO expander communicates with the Raspberry Pi using the I2C protocol.
- The color module takes in strings representing color in various formats (#FFF, rgb(255,255,255), and translates them into a red, green, and blue channel that our Pi and LED understand.
- The REPL helps with debugging by letting you see and manipulate the state the bot is in. It is powerful because most robotics platforms have a way of altering the state of the code while running.
Hands-On Robotics with JavaScript
By :
Hands-On Robotics with JavaScript
By:
Overview of this book
JavaScript has an effective set of frameworks and libraries that provide support for embedded device programming and the robotics ecosystem. You’ll be able to put your JavaScript knowledge to work with this practical robotics guide.
The book starts by guiding you in setting up an environment to program robots with JavaScript and Rasberry Pi 3. You will build beginner-level projects, such as a line-following robot, and then upgrade your robotics skills with a series of projects that help you get to grips with the Johnny-Five library. As you progress, you’ll learn how you can improve your projects by enabling advanced hardware components and programming concepts. You’ll even build an advanced AI-enabled robot, connect its NodeBots to the internet, create a NodeBots Swarm, and explore Message Queuing Telemetry Transport (MQTT).
By the end of this book, you will have enhanced your robot programming skills by building a range of simple to complex projects.
Table of Contents (19 chapters)
Title Page
Dedication
Packt Upsell
Contributors
Preface
Free Chapter
Setting Up Your Development Environment
Creating Your First Johnny-Five Project
Building Interactive Projects with RGB LED
Bringing in Input with Buttons
Using a Light Sensor to Create a Night-Light
Using Motors to Move Your Project
Using Servos for Measured Movement
The Animation Library
Getting the Information You Need
Using MQTT to Talk to Things on the Internet
Building a NodeBots Swarm
Assessments
Other Books You May Enjoy
Index
Customer Reviews