Book Image

Raspberry Pi 3 Cookbook for Python Programmers - Third Edition

By : Steven Lawrence Fernandes, Tim Cox
Book Image

Raspberry Pi 3 Cookbook for Python Programmers - Third Edition

By: Steven Lawrence Fernandes, Tim Cox

Overview of this book

Raspberry Pi 3 Cookbook for Python Programmers – Third Edition begins by guiding you through setting up Raspberry Pi 3, performing tasks using Python 3.6, and introducing the first steps to interface with electronics. As you work through each chapter, you will build your skills and apply them as you progress. You will learn how to build text classifiers, predict sentiments in words, develop applications using the popular Tkinter library, and create games by controlling graphics on your screen. You will harness the power of a built in graphics processor using Pi3D to generate your own high-quality 3D graphics and environments. You will understand how to connect Raspberry Pi’s hardware pins directly to control electronics, from switching on LEDs and responding to push buttons to driving motors and servos. Get to grips with monitoring sensors to gather real-life data, using it to control other devices, and viewing the results over the internet. You will apply what you have learned by creating your own Pi-Rover or Pi-Hexipod robots. You will also learn about sentiment analysis, face recognition techniques, and building neural network modules for optical character recognition. Finally, you will learn to build movie recommendations system on Raspberry Pi 3.
Table of Contents (23 chapters)
Title Page
Copyright and Credits
Dedication
Packt Upsell
Contributors
Preface
Index

Configuring your network manually


If your network does not include a DHCP server or it is disabled (typically, these are built into most modern ADSL/cable modems or routers), you may need to configure your network settings manually.

Getting ready

Before you start, you will need to determine the network settings for your network.

You will need to find out the following information from your router's settings or another computer connected to the network:

  • IPv4 address: This address will need to be selected to be similar to other computers on the network (typically, the first three numbers should match, that is, 192.168.1.X if netmask is 255.255.255.0), but it should not already be used by another computer. However, avoid x.x.x.255 as the last address, since this is reserved as a broadcast address.
  • Subnet mask: This number determines the range of addresses the computer will respond to (for a home network, it is typically 255.255.255.0, which allows up to 254 addresses). This is also sometimes referred to as the netmask.
  • Default gateway address: This address is usually your router's IP address, through which the computers connect to the internet.
  • DNS servers: The Domain Name Service (DNS) server converts names into IP addresses by looking them up. Usually, they will already be configured on your router, in which case you can use your router's address. Alternatively, your Internet Service Provider (ISP) may provide some addresses, or you can use Google's public DNS servers at the addresses 8.8.8.8 and 8.8.4.4. These are also called nameservers in some systems.

For Windows, you can obtain this information by connecting to the internet and running the following command:

ipconfig /all

Locate the active connection (usually called Local Area Connection 1 or similar if you are using a wired connection, or if you are using Wi-Fi, it is called a wireless network connection) and find the information required, as follows:

The ipconfig/all command shows useful information about your network settings

For Linux and macOS X, you can obtain the required information with the following command (note that it is ifconfig rather than ipconfig):

ifconfig

The DNS servers are called nameservers and are usually listed in the resolv.conf file. You can use the less command as follows to view its contents (press Q to quit when you have finished viewing it):

less /etc/resolv.conf

How to do it...

To set the network interface settings, edit /etc/network/interfaces using the following code:

sudo nano /etc/network/interfaces

Now perform the following steps:

  1. We can add the details for our particular network, the IP address number we want to allocate to it, the netmask address of the network, and the gateway address, as follows:
iface eth0 inet static  address 192.168.1.10  netmask 255.255.255.0  gateway 192.168.1.254
  1. Save and exit by pressing Ctrl + X, Y, and Enter.
  2. To set the name servers for DNS, edit /etc/resolv.conf using the following code:
sudo nano /etc/resolv.conf
  1. Add the addresses for your DNS servers as follows:
nameserver 8.8.8.8nameserver 8.8.4.4
  1. Save and exit by pressing Ctrl + X, Y, and Enter.

There's more...

You can configure the network settings by editing cmdline.txt in the BOOT partition and adding settings to the startup command line with ip.

The ip option takes the following form:

ip=client-ip:nfsserver-ip:gw-ip:netmask:hostname:device:autoconf
  • The client-ip option is the IP address you want to allocate to Raspberry Pi
  • The gw-ip option will set the gateway server address if you need to set it manually
  • The netmask option will directly set the netmask of the network
  • The hostname option will allow you to change the default raspberrypi hostname
  • The device option allows you to specify a default network device if more than one network device is present
  • The autoconf option allows the automatic configuration to be switched on or off