Now that we have our operating system running, we can really start to thinking about the portability advantages this Raspberry Pi Zero can bring. We'll start talking to the Raspberry Pi Zero, get it on the network, and look at the unique features and modes you get with the Zero's small form factor.

If you already have a computer that you use at home, the Raspberry Pi Zero will probably not be serving as a replacement. Wouldn't it be nice if you could work with the Zero through your own home computer? Then you only need one mouse, one keyboard, and one monitor. This recipe will show you how to use the Raspberry Pi Zero's UART GPIO to communicate with a USB-to-serial interface. Becoming familiar with this interface is great for troubleshooting (for example, when USB isn't working or you don't have a monitor nearby) and is one many different ways you can interact with your Zero.

An easy way to communicate with your Pi and get your little computer connected to the Internet is connecting it to a USB Wi-Fi adapter. Once you have your Raspberry Pi Zero connected to Wi-Fi, we can get it to interact with pretty much anything that lives on your home network.

Getting ready

For this recipe, you will need your Raspberry Pi Zero, a USB OTG adapter, and a USB Wi-Fi device. Most of this equipment comes with any starter kit and is inexpensive to buy individually-the OTG adapters can be found for less than $5 and Wi-Fi dongles are $10-$15. It is still amazing that a lot of these accessories cost at least as much as the computer they are needed for!

A small USB OTG dongle and Wi-Fi adapter make for a pretty small setup:

You do need to add power, but even with that, you maintain a very small footprint for what will be an Internet-enabled computer.

The embedded Linux site ( elinux.org ) has a comprehensive listing of tested and compatible Wi-Fi cards...

The USB dongle solder hack is considered one of the very first hacks shared in the community after the release of the Raspberry Pi Zero. With such a small form factor and USB OTG connectors, many hackers didn't like the idea of adding to the size of the board with an adapter and then tacking on a USB dongle. This recipe shows you how to attach an uncased Wi-Fi adapter to the Raspberry Pi Zero to keep your footprint still small enough to fit a mints tin.

Now that we have our Raspberry Pi Zero on the network, let's look a little closer at what we can do with the networking. Everything should have connected to your Wi-Fi network thanks to DHCP (Dynamic Host Allocation Protocol). DHCP takes incoming requests from devices to be added to the network. It has a pool of IP addresses on the network that it will "lease" to the device for a period of time. After the lease expires, the device may renew (and, depending on the DHCP server rules, will get a new or the same address), or the address will be returned to the available pool. This makes it easy to add machines to a network without keeping track of individual addresses assigned to devices. When your Raspberry Pi Zero connected to your Wi-Fi network, by default, it would have been assigned at least one IP address: an IPv4 address (four sets of numbers between 0 and 255, as in 192.168.17.250), and/or a newer IPv6 address (8 sets of hexadecimal numbers...

Now that we have our computer on the network, we want to make sure other computers are able to contact it. The ping command is one of the first tests to tell whether your computer can be contacted. The command sends a small test packet of data to another computer's IP address or hostname and waits to hear a response. If it does, it tells you how long it took for the response to come back. If it doesn't, it tells you it is not receiving a response.

The ideal way to talk to your Raspberry Pi Zero is using Secure SHell (SSH). This gives you a secure, encrypted channel to talk to your Pi from anywhere on the network. For example, let's say you want your Pi to collect temperature information from your attic and make it available on your home network. You don't want to drag a monitor, mouse, and keyboard up to your attic every time you want to make a change-you want to do it from your regular home computer! If you have your RPZ using Wi-Fi, on the network, and ping-able, the next step is to work with it remotely over SSH. Here's how.

While it is inevitable that you will use the command line a lot when using Linux, a lot of people enjoy Raspbian's GUI. But you still want to keep your Zero in the attic! No problem at all: the Virtual Network Computing (VNC) service makes the GUI available from anywhere you able to connect.