Chris Greening's Raspberry Pi Zero 2 W Doom Machine Needs No Wires, Thanks to a Charging Coil

Maker Chris Greening is not the first to play Id Software's seminal first-person shooter Doom on a Raspberry Pi Zero 2 W single-board computer (SBC), but he may be the first to do so entirely without wires — by integrating a wireless power coil into the build.

"Ever since discovering these crazy wireless LEDs I've been messing around with wireless charging technology. So far I’ve been a bit disappointed with what I’ve been able to do," Greening writes of the project. "It's been great for making LEDs light up, but my attempts to use it for anything serious have either resulted in me burning out the transmitters, or releasing the magic smoke from the circuit I’m trying to power. So I decided to bite the bullet and get a proper set of wireless charging PCBs."

While the off-the-shelf wireless charging circuits — which operate in the same way to those of powered toothbrushes, with the charging coil inducing a current in the receiving coil when the two are brought into close contact — proved a lot more reliable than Greening's home-brew efforts, the maker was still searching for a project to prove their capabilities. Enter Id Software's Doom, a first-person shooter from 1993 which has become infamous for its ability to run on a wide variety of hardware — including the low-cost Raspberry Pi Zero 2 W single-board computer.

"I thought it might be fun to try and run a Raspberry Pi Zero 2 W with the transmitter and receiver boards. To make it a real test I’m going to run Doom on the Pi with a nice TFT screen. To check if this was even feasible I ran the Pi with it connected to my USB [power] monitor and it peaks at around 0.65Amps when running Doom. So it should work without any problems."

Having tested the charging circuit's peak sustainable output, and ensuring the best possible alignment using magnetic sheets, Greening found the game running perfectly from wireless power — though, naturally, the machine switched off as soon as it was lifted from the charging pad. The solution to that: a small battery, which could be charged wirelessly for use on-the-go. "With the battery hooked up," Greening explains, "it charges up via the wireless transmitter. And eventually the battery gets up to full charge."

More information on the project is available in the video above or on Greening's website.