The Pi Zero is a fantastic little computer, supposing, of course, you can get your hands on one. Stocks are still quite limited despite massive amounts of recent production. With the Zero and its compact size, you now have the very real potential to take your retro gaming experience on the road with a portable device. But there are lots of upsides and downsides you have to know before that dream comes true.
Performance
Obviously the first question is will it run Retropie at all, given that it’s a cut down Pi? The short answer is yes; it runs it and runs it very well. The slightly longer answer is that while the processor is the same as in the original slow Pi, it’s been newly reconfigured to run at 1GHz, and the low power overheads built into the new board make it run both fast and usably cool.
Retropie runs very well on the Pi Zero with the proviso that the games you run are the older sorts of consoles like older arcade machines and early consoles and computers like the NES, SNES, MegaDrive and Master System, Commodore 64 and Sinclair Spectrum. Running graphics-hungry modern consoles like the Playstation or N64 are possible, but the emulated performance is nowhere near up to the speed of the original machines with their custom chips. They stutter and stop and are effectively unplayable. This is also true of the Pi1 and Pi2.
Desktop or TV Use
Easiest, of course, is desktop or TV use, as with all the other Pi computers, with the downside that you are tethered to a power supply, TV monitor of some kind and a joystick/gamepad and (optionally) a keyboard. Obviously you need adapters for the micro USB ports while doing this.
Some kind of USB hub is necessary if you want to run a keyboard (to use MAME for example) because the Zero has only one USB input. This will need to be powered, too, as the Zero has no power overhead for taking on powering a USB hub or any other device for that matter.
A USB hub is also necessary for file transfer, as you need both a USB stick and a joystick (and ideally a keyboard, too) to do transfers. You can store the game ROMs on a USB stick on your desktop computer then transfer them to the Zero via USB and the File Transfer menu in the Retropie system. Using the Zero tethered is an ideal and fast solution as you don’t need to make additional portable arrangements for sound and power.
Portable Use
Using a small, light and low-power Pi Zero for your retro gaming does raise the option of portable gaming, as the Pi Zero can comfortably fit inside almost any retro handheld game console case.
The primary challenges are battery power, screen, charging circuit/power supply and sound output. You can power the Pi from any USB battery. Getting a battery that powers it is not the problem; this one, for example, is ideal. Charging that battery inside the case is the problem, but we’ll cover that in a second. There are many small screens which will fit inside retro devices, like this one , this one, this one and this one. You should replace the screen. Yes, it’s tempting if you are hacking an existing console to use the screen inside the donor case. Please don’t. Using the existing screen is problematic because you need to power it, and you need to know its specification. It’s much better to buy a cheap, small replacement LCD which you know is compatible, higher resolution, has lower power needs, and has fewer or no dead pixels. It will be brighter than a display that’s more than twenty years old and has seen some heavy use.
It’s important to know the difference here between a battery and a power supply. A battery supplies electricity, constantly, all day, without any moderation or consequences. A power supply is like the brain of a battery, facilitating charging of the battery and being aware of when it’s charged, so you need a power supply/battery combination. A common part used for this purpose is the Power Boost 1000C which is a perfect solution for powering a Pi to make a portable device. Finally there is the problem of getting sound out of the Zero. Normally the only sound output is through HDMI. There is a way to get the sound coming out of the GPIO, but it’s complicated. You have to add resistors and reroute the audio signal. This is the only way to do it if you want to make a portable Pi with sound. Sadly most people get around this limitation by leaving their Pi Zero Portable silent. A possible solution (although it adds size and the problem of supplying power for the hub ports) is to add a USB hub and use a USB sound card which you can buy for a few cents almost anywhere. This is not ideal, but it will work.
Conclusion
We hope that got you started down the road of using your Raspberry Pi Zero for retro gaming, both at home and on the road. At some point in the next few months we’ll be showing you how to build a Retropie console from scratch and also a video tutorial in our Premium area. Stay tuned for that. If you have any questions about Pi Zero or Retropie, please let us know in the comments below.
