To get your Raspberry Pi Zero online on HDMI, the following equipment will be needed:

Take a look at your Raspberry Pi Zero and examine each of the connections. They really fit a lot into a small space:

Raspberry Pi components

The numbers in the figure denote the following components:

The back side of the board contains test connector points:

Raspberry Pi Zero test pads

Not all the test points are documented for the Raspberry Pi Zero, but several are known:

Test points are great for validating that your Raspberry Pi is seeing the right voltage and/or frequencies. Many of the test points require an oscilloscope to observe and are thus beyond the scope of this book, but testing and troubleshooting prototypes is as easy on a Raspberry Pi Zero as it is on one of the larger boards.

You can also power your Raspberry Pi Zero over the GPIO ports, though it is important to be careful to have consistent and predictable power so you don't fry your board. The easiest method is certainly to find steady 5V source that works over micro-USB, but with careful design, you can run your board from any power supply with consistent 5 V and current up to 1 A. We will run our Raspberry Pi Zero on batteries later in this cookbook.

Of course, as you add peripherals, there will be a need to draw more current. If on USB, using a powered USB port will help a lot. When working with devices you have connected directly to GPIO, you just need to make sure your Raspberry Pi Zero power source can provide enough current to run the board and what's attached to it.

Until you have an SD card ready, you won't really be able to test the power completely - you can plug the adapter into the Raspberry Pi, but keep it unplugged from the power for now.

On the Raspberry Pi website, the Downloads page offers both a full version (offline install) and a "Lite" (network install) version of the images. Select the full version when setting up the Raspberry Pi Zero, as you will not have network connectivity right away to download the parts missing from the Lite version. Once you have the full version installed, it is easy to get networking configured and everything updated, which we will cover later in the book. Download the latest full version of NOOBS from the Raspberry Pi website, and unzip it to a new directory. After the extraction is complete, you are ready to move on to the next recipe to install NOOBS on your SD card.

Just click on Download ZIP from a browser, and it will automatically begin:

The NOOBS download and SHA-1 signature

This is where you'll need your SD card. A 4-GB card is the minimum, but as card prices have dropped a lot over the years, I'd recommend an 8-GB or 16-GB card. I also always recommend hackers to get a couple of cards (for example, get two 8-GB cards instead of one 16-GB card), so you can always have a spare card to write a test operating system to while you have the other SD card in use. If you really get into Raspberry Pi development, you will find having spare SD cards a must.

If you are a Linux user, you should just skip ahead to the Raspbian installation on Ubuntu.

If you are an OS X or Windows user, you can use the SDFormatter utility from the SD Association ( https://www.sdcard.org/downloads/formatter_4/ ) to format your SD card:

The SDFormatter SD card utility

Once your card is formatted, copy the files from your extracted NOOBS download from the last recipe to the newly formatted SD card. Once this is done, you will be ready to finish building your Raspberry Pi Zero.

Once you've downloaded the file, unzip it and copy it to your SD card:

Installing NOOBS is as simple as copying files to a formatted SD card

Writing a Raspbian SD card without NOOBS: If you want to skip the NOOBS setup and jump right into Raspbian or if you want to try out a different distribution to see how it works on your Raspberry Pi Zero, there are some great tools available to make this easy to do. First, you need to download the Raspbian image file from the Raspberry Pi website ( https://www.raspberrypi.org/downloads/raspbian/ ). Unzipping the file creates a single, larger file, called the image file. Be sure to download the full file, not the Lite version, as you will be starting without a network connection.

On a Windows machine, the Win32 Disk Imager (https://sourceforge.net/projects/win32diskimager/ ) is an easy-to-use open source project for taking image files and writing them to your SD card. Insert your SD card, and select the unzipped image file you downloaded from the Raspberry Pi site:

Win32 Disk Imager for Windows

Once you have verified that you've selected the right .img file and the correct drive letter associated with your SD card, click on Write and wait for the process to finish. Once it completes successfully, eject the card and it will be ready to start your Raspberry Pi Zero.

The process for validating and copying a NOOBs installation on OS X is fairly straightforward:

The output will be similar to this:

dd command input and output

After several minutes, your card will be ready to go!

Whichever way you decided to set up your SD card, you are just a few connections away from getting your Raspberry Pi Zero online!

If you just want to get started with HDMI, this is not a required recipe, and you can skip ahead. You will need:

You will need a micro-USB OTG adapter. One end is the male micro-USB to connect to the Raspberry Pi Zero, and the other end is the female standard USB to connect devices (such as mice or keyboards). You'll also want a powered USB hub.

A typical USB OTG adapter will look like this:

Micro-USB OTG adapter

A USB OTG cable is really a must-have when starting out with the RPZ. It converts the micro-USB male connections to a standard USB female connection. With that and a powered USB hub, you will have no problem connecting a keyboard, mouse, USB storage, or devices such as Wi-Fi or Bluetooth. We will look at different ways of implementing more low-profile things such as Wi-Fi later, but a hub is the easiest way to get started.

All you need to do here is connect your OTG adapter to your Raspberry Pi Zero, and then, your powered USB hub to the other end of the OTG adapter. On your hub, connect your keyboard and mouse. Before too long, we will have the hub filled with peripherals, and then we will look at better ways to access (and accessorize!) the Raspberry Pi Zero.

Now that you have your USB set up, your final step is getting video output. If you went with the video RCA hack, you can use the HDMI port or RCA video to get going. For HDMI, you'll need a micro-HDMI to standard HDMI adapter (and standard HDMI cable), or an HDMI cable that has one end micro and the other end standard.

A typical standard-to-micro HDMI adapter looks like this:

Standard-to-micro HDMI adapter

We now have our HDMI adapter and cable connected, the SD card installed, and the USB OTG adapter ready to go:

Pi connected to USB OTG and HDMI

This breaks down to fields separated by a colon (:):

Before logging on as your new user, you might want to give them the ability to do superuser things, like the pi account does. Let's take a look at how to give your new user more powers!

To give your user the ability to run as a superuser, use the visudo tool:

sudo visudo

This opens an edit window of the sudoers file, which will allow you to give your new user special permissions. Look down to where the pi user is already set up, and add rpz ALL=(ALL) ALL, like this:

#includedir /etc/sudoers.d
pi ALL=(ALL) NOPASSWD: ALL

rpz ALL=(ALL) ALL

This gives your user the same permissions as the pi user, but requires that you enter a password when executing something that requires elevated permissions. This way, you can prevent the unauthorized execution of things that only a superuser should execute.

You can try logging in as our new user and trying to sudo. The touch command creates an empty file wherever you tell it to. If you don't have permissions to write, the touch command will fail. We will try logging on as our rpz user and trying touch with and without sudo, in a directory that requires elevated permission to write to. Use the su command to log on as another user:

pi@rpz14101:~ $ sudo su - rpz
rpz@rpz14101:~ $ touch /opt/testsudo.deleteme
touch: cannot touch '/opt/testsudo.deleteme': 
      Permission denied
rpz@rpz14101:~ $ sudo touch /opt/testsudo.deleteme
[sudo] password for rpz:
rpz@rpz14101:~ $ ls /opt
minecraft-pi  pigpio  sonic-pi  testsudo.deleteme
      vc  Wolfram

Excellent! You now have superuser abilities (but remember, Spider-Man, with great power comes great responsibility), and whoever is executing them needs to know your password (which is only you, of course). If you'd prefer to keep the permissions the same as the pi user, you can sudo visudo the permissions again and set your user's settings to NOPASSWD: ALL, just like for the pi user.

There is a collection of user and group commands you can use beyond adduser: addgroup, usermod, and userdel are all good things to put in your administrator's toolbox. For pretty much any Linux command, adding --help (for example, useradd --help) or prefixing with man (man useradd) will provide you with instructions and options for what you can do with it:

rpz@rpz14101:~ $ useradd --help
Usage: useradd [options] LOGIN
       useradd -D
       useradd -D [options]
Options:
  -b, --base-dir BASE_DIR       base directory for 
        the home directory of the
                                new account
  -c, --comment COMMENT         GECOS field of the 
        new account
  -d, --home-dir HOME_DIR       home directory of 
        the new account
  -D, --defaults                print or change 
        default useradd configuration
  -e, --expiredate EXPIRE_DATE  expiration date of 
        the new account
  -f, --inactive INACTIVE       password inactivity 
        period of the new account
  -g, --gid GROUP               name or ID of the 
        primary group of the new
 account
  -G, --groups GROUPS           list of 
        supplementary groups of the new 
account
  -h, --help                    display this help 
        message and exit
  -k, --skel SKEL_DIR           use this alternative 
        skeleton directory
  -K, --key KEY=VALUE           override 
        /etc/login.defs defaults
  -l, --no-log-init             do not add the user 
         to the lastlog and
 faillog databases
  -m, --create-home             create the user's 
        home directory
  -M, --no-create-home          do not create the 
        user's home directory
  -N, --no-user-group           do not create a 
        group with the same name as
the user
  -o, --non-unique              allow to create 
        users with duplicate
(non-unique) UID
  -p, --password PASSWORD       encrypted password 
        of the new account
  -r, --system                  create a system 
        account
  -R, --root CHROOT_DIR         directory to chroot 
        into
  -s, --shell SHELL             login shell of the 
        new account
  -u, --uid UID                 user ID of the new 
        account
  -U, --user-group              create a group with 
        the same name as the user
  -Z, --selinux-user SEUSER     use a specific 
        SEUSER for the SELinux user mapping