Okay, so you are convinced: You see how cool the Raspberry Pi is, and you are ready to take the next step and turn that $35, credit card-sized circuit board into your next electronic masterpiece.
Where do you begin, though? You were told that the $35 buys you the Raspberry Pi, but literally nothing else. What do you need to get started with Raspberry Pi projects? Where do you buy (or find) the stuff?
Worry no more, faithful reader. By the time you finish reading this article, you'll have all the knowledge you need to begin your descent into the wild and wonderful world of Raspberry Pi hardware and software engineering. Shall we get started?
Your Raspberry Pi Shopping List
Because I'm a big fan of summary lists, let me begin by providing you with the punch list of components that you'll need to start work with your Raspberry Pi:
- Raspberry Pi Model A or Model B board (B is preferred)
- Micro USB 5V, 700mA power supply
- 4GB or greater Secure Digital (SD) card
- Powered USB hub
- USB keyboard and mouse
- HDMI monitor and cable
- Audio cable
- Ethernet cable or Wi-Fi dongle
Now that you know precisely how many things you need to have ready on the front end, please allow me to give you a bit more explication on each one.
Raspberry Pi Hardware
The Raspberry Pi board comes in two varieties. The Model A board costs $25, and the Model B costs $35. However, for my money you'll want the Model B board in almost all cases.
Why? Well, for starters, the Model B board has twice the random access memory (RAM) as the Model A. The Model B also includes an on-board Ethernet jack and an extra USB port. That's a lot of extra hardware for 10 dollars.
If the Model A has an advantage, it is its minimal power consumption. Some hobbyists choose the Model A if they have projects that require low power draw, like, say, a battery-operated weather station or motion detector.
The Raspberry Pi Model B draws 700 milliamps (mA) of power, so it is imperative that you purchase a power supply with a rating of at least that value. Although the Pi operates internally at 3.3V, the device expects an incoming voltage of 5V.
Some folks get away with dual-purposing their eBook reader's or cell phone's power supply with the Raspberry Pi. This should not be a problem so long as you keep the numbers I gave you in mind.
I show you both a representative power supply as well as a powered USB hub in Figure 1.
Figure 1 A Raspberry Pi-compatible power supply is at left, and a 7-port powered USB hub is at right
Here are a couple power supplies from a source that I know and trust:
The Raspberry Pi has no internal hard drive. Instead, you run the Linux operating system and all apps from a standard-sized SD card. I suggest that you choose a name brand card of at least 4GB in capacity and with a speed class rating of at least 4. Here are some suggestions:
Powered USB Hub
Strictly speaking, you don't absolutely need a powered USB hub to get work done with the Raspberry Pi. However, having one on hand makes your life so much easier. Think of it this way: Everything you plug into the Raspberry Pi's USB ports draws power from the Pi.
Depending upon the rating of your power supply, you may not have a lot of extra power to go around. Another point to consider is that you may have need of more than 2 USB ports.
The bottom line is that you should spend the money for a powered hub. This way you can plug in your keyboard, mouse, Wi-Fi dongle, and an external USB drive and still have ports (and power) left over.
USB Keyboard and Mouse
Depending upon how your home network is set up, you may not need a dedicated keyboard and mouse for your Pi because you can connect to the device remotely over its network connection.
However, you will need the keyboard and mouse at least initially to make a connection to the Pi, set up your operating system, and the like. Here are some cool sources for specialized hardware:
HDMI Monitor and Cable
Again, you may be able to connect to your Pi remotely over the network and display its output on your usual computer monitor. However, if you want the Pi to have its own dedicated display, then you'll need an High Definition Multimedia Interface (HDMI) cable to connect it to a compatible monitor or television. Here are some sources:
The audio capabilities of the Raspberry Pi are impressive, allowing you to output the audio signal via an optical audio cable to speakers.
If you have a Model A board, then your choices for networking are a Wi-Fi USB dongle and that's it. However, if you have a Model B, you can also take advantage of the wired RJ-45 Ethernet jack that is soldered to the circuit board.
You can see what a representative USB Wi-Fi dongle looks like alongside a case-bound Raspberry Pi board in Figure 2.
Figure 2 A Raspberry Pi in a case is at left, and a verified Wi-Fi USB dongle is at right. The presence of the Ethernet port and 2 USB interfaces denote the Pi as a Model B board
You'll want to make sure that you choose a Wi-Fi dongle that is certified to work with the Raspberry Pi. To that point, please bookmark the RPi Verified Peripherals Web page, that hosts a robust hardware compatibility index for the Pi.
Once you've amassed all of the required hardware, you need to install a distribution of the Linux operating system so you can actually use your Raspberry Pi.
If you haven't decided upon a particular distribution, then I suggest you try out the New Out of Box Software (NOOBS) package from the Raspberry Pi Web site. I show you the NOOBS interface in Figure 3.
Figure 3 The NOOBS tool gives you one-click installation of a number of different Raspberry Pi-optimized Linux distributions
To write an operating system to your SD card, you'll need SD card writer software. Here are my suggestions based upon the operating system on your main computer:
The beauty of open source software means that all of this software I'm referring you to is absolutely free — awesome!
Useful Optional Components
As time goes on, you'll doubtless begin to think of neat project ideas for your Raspberry Pi. Everything we talked about in this article and more is included in my book on the subject, Hacking Raspberry Pi, by Que Publishing.
In the meantime, I want to leave you some pointers for optional hardware that you can get a heck of a lot of use out of in your Raspberry Pi experimentations.
You know how everyone has their own custom, cool-as-all-get-out case for their iPhone? Yeah — the same business model exists for the Raspberry Pi. One caveat: make sure to choose a case that not only looks good but also provides protection for the Pi and gives the tiny circuit board adequate airflow.
You can take just about any USB webcam, plug it into your Pi, and with minimal system configuration have yourself a portable Web-based webcam server, security camera, or something else.
The Arduino is an incredible little device. On its surface it looks like a Raspberry Pi, but the Arduino is actually a microcontroller instead of a full-fledged microcomputer and therefore has its own particular "skill set." As it happens, you can link the Pi and the Arduino as well as program and transfer sketches directly to the Arduino from the Pi's operating system environment.
I show you the Raspberry Pi and the Arduino Uno lying next to each other and ready to rock in Figure 4.
Figure 4 A Raspberry Pi Model B microcomputer at left, and an Arduino Uno microcontroller at right
Motors and Robotics
Who doesn't love using electronics to make stuff move and create robots? I sure do. Accordingly, many third-party vendors sell pre-configured kits to make delving into the fascinating study of motor controllers and robotics a reality with the Raspberry Pi. Here are some references:
Now that you have the right gear and some ideas for additional equupment, it's time to start building! Look to my book, Hacking Raspberry Pi, for more inspriration and project ideas. For a sample, check out chapter 3, A Tour of Raspberry Pi Peripheral Devices.