5. Port Input and Output on the Raspberry Pi | Raspberry Pi Essentials

Sign In Start Free Trial

Book Overview & Buying
Table Of Contents
Feedback & Rating

Raspberry Pi Essentials

By : Jack Creasey

3.8 (5)

Raspberry Pi Essentials

3.8 (5)

By: Jack Creasey

Overview of this book

Programmers new to the Raspberry Pi and novice programmers with little to no experience with micro board computing will find the book useful. A basic knowledge of programming languages in general will prove useful for a better understanding of the topics.

Preface

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Free Chapter

1. Getting Started with Raspberry Pi

1. Getting Started with Raspberry Pi

Let's get started

Unboxing the Raspberry Pi

Local display, keyboard, mouse, or remote headless access

Selecting a screen

Getting your SD Card ready

Booting the Raspberry Pi for the first time

A quick tour of the desktop

Instructions for downloading all project files

Summary

2. Configuring the Raspberry Pi Desktop and Software

2. Configuring the Raspberry Pi Desktop and Software

Hardware and software networking configuration

Configuring the Raspberry Pi desktop and software

Desktop and file manager accelerators

Project 1 – Building a talking clock with a Bash script

Building a talking clock with Python 3

Summary

3. Raspberry Pi and Cameras

3. Raspberry Pi and Cameras

Connecting cameras to the Raspberry Pi

PiCam and PiNoIR

Webcams

Project architecture for the Raspberry Pi security camera

Features and limitations of the cameras

Project 1 – Running raspivid as a background service

Project 1a – Creating a Bash script to drive raspivid

Project 1b – Creating a movement detector with a USB camera

Project 2 – Combining the webcam movement detector and the PiCam camera

Project 3 – Creating a simple Python GUI for the security application

Summary

4. Raspberry Pi Audio Input and Output

4. Raspberry Pi Audio Input and Output

Audio quality and bandwidth

Audio capability on the Raspberry Pi

Understanding the ALSA configuration

Configuring the Raspberry Pi to support high-quality sound

Project 1 – Installing an advanced audio playback application

Building an Internet radio based on VLC and Raspberry Pi

Project 2a – Running VLC in the background for the Internet radio

Project 2b – Designing a playlist file for the Internet radio

Project 2c – Parsing the playlist file for the Internet radio

Project 2d – Implementing a Python text interface to VLC

Project 3 – Implementing a TKinter GUI for the Internet radio

Recording sound files on the Pi

Summary

5. Port Input and Output on the Raspberry Pi

5. Port Input and Output on the Raspberry Pi

Understanding Raspberry Pi digital input and output ports

Driving LEDs as output indicators

TKinter LED demo

TKinter switch demo

Adding a physical switch interface to the Internet radio

Project 1 – Add a switch interface to the Internet radio

Summary

6. Driving I2C Peripherals on the Raspberry Pi

6. Driving I2C Peripherals on the Raspberry Pi

Getting started with I2C

Project 1 – Python control of a PWM board driving RC servo motors

Summary

7. Going Mobile with Raspberry Pi

7. Going Mobile with Raspberry Pi

Remote access to the Raspberry Pi

Remote access from Linux and OSX

Testing your remote session from a PC or Mac

Battery power systems

Project 1 – Selecting a project battery capacity

Summary

8. Creating a Raspberry Pi Line-following Robot

8. Creating a Raspberry Pi Line-following Robot

Implementing a line-following robot

Line-following robot architecture

Implementing rbuttons.py

Implementing rwheel.py

Implementing navigate.py

Steering algorithm

Time to build the mobile system

Line-following robot

Summary

Index

Index

Customer Reviews

3.8 (5)

5 star

0

4 star

80%

3 star

20%

2 star

0

1 star

0

TKinter switch demo

Since the action code for Python is so similar to that for TKinter, we will go directly to a TKinter interface for switch sensing. Since the plan is to eventually create push buttons for our Internet radio, let's show the breadboard schematic that we need to achieve this:

Note

Warning: While the schematic shown is quite OK for breadboard use, it is not suitable where the wires to the switches are long (greater than a few inches). Notice that the GPIO pin would be exposed directly to any fault conditions. It is advisable to put at least a 1k Ohm series resistor to the GPIO pin. Never run the 5 Volt or 3.3 Volt supply through a long line to the switch (or LED location) as this directly exposes the supply to any potential wiring faults.

In preparation for the demo, complete the following:

Download the tkswitch21.py code from http://1drv.ms/1ysAxkl.
Store the tkswitch21.py file in /home/pi/gpio.
Run the code using IDLE3 by starting from a command line with sudo idle3 (remember...

Search

Your notes and bookmarks