Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Hands-On Internet of Things with MQTT

You're reading from   Hands-On Internet of Things with MQTT Build connected IoT devices with Arduino and MQ Telemetry Transport (MQTT)

Arrow left icon
Product type Paperback
Published in Oct 2019
Publisher Packt
ISBN-13 9781789341782
Length 350 pages
Edition 1st Edition
Languages
Tools
Arrow right icon
Author (1):
Arrow left icon
Tim Pulver Tim Pulver
Author Profile Icon Tim Pulver
Tim Pulver
Arrow right icon
View More author details
Toc

Table of Contents (16) Chapters Close

Title Page
Copyright and Credits About Packt Contributors Preface 1. The Internet of Things in a Nutshell FREE CHAPTER 2. Basic Architecture of an IoT Prototype 3. Getting Started with MQTT 4. Setting Up a Lab Environment 5. Building Your Own Automatic Pet Food Dispenser 6. Building a Smart E-Ink To-Do List 7. Building a Smart Productivity Cube, Part 1 8. Building a Smart Productivity Cube, Part 2 9. Presenting Your Own Prototype 1. Assessments 2. Other Books You May Enjoy

Optimizing the dispenser code

Now, let's get back to coding. You probably tried out how the dispenser works with real material in it, controlled by sending commands as 1 and 0 over the Serial Monitor. Sending two commands to manually open and close the opening is not super useful.

Let's modify our code so that the servo automatically goes back to the closed position after x milliseconds. If you use a very fine material (such as sugar), this might be something like 150 milliseconds. For grainier material (dry cat food, for example), something in the seconds might be good. Remember, we always need to specify the time in milliseconds, so 2 seconds would be 2,000 milliseconds.

Save the existing sketch as a copy with the name ch5_02_servo_serial_auto_close.

To automatically close the cap shortly after it is opened, we need to add a few new variables. Follow these steps...

lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at $19.99/month. Cancel anytime
Banner background image