Nintendo's Game & Watch hacked and turned into retro emulation beast — Solder job unlocks device from its Zelda-only cage thanks to a custom SD card slot
A true pocket console!
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Before there ever was a Game Boy, Nintendo had the Game & Watch, the company's first successful handheld that invented the D-pad. Since the original Donkey Kong G&W, Nintendo has done modern re-releases as recently as 2021 when the Zelda edition came out to celebrate the franchise's 35th anniversary. Now, on Zelda's 40th birthday, an enthusiast has decided to take that Game & Watch and mod it into a proper retro emulator.
Unlike the original Game & Watches for the 80s, the re-release got an updated color LCD and came loaded with classic games, powered by a USB-C port. The battery and controls are also updated to reflect current times, which means there's a pretty decent base here for a portable handheld. The open-source community has done a lot to unlock G&W's full potential, and this project from Macho Nacho Productions is built on their shoulders.
The mod starts with taking apart the G&W, disconnecting all the ribbon cables, and desoldering the speaker. Then, the firmware stored on the motherboard is dumped, modified, and flashed back onto the memory chip to essentially jailbreak it. Unfortunately, this chip is only 16 MB, which is not enough to push the payload through, so the process required replacing it with a 64 MB IC. That comes later, though; they actually need the files from this chip.
An ST-Link V2 programmer was then connected to the motherboard by soldering it to the relevant pads. This is what enables communication between a computer — which will retrieve and mod the firmware — and the Game & Watch. Once that was done, Macho Nacho upgraded the memory chip, and it was time to flash the custom firmware.
Lots of PowerShell windows later, the process was completed, and the programmer was removed from the motherboard. He was not quite done with the hardware side of things yet, as even though the custom firmware worked, it still needed to read from something, and that meant adding a microSD card slot to the Game & Watch.
This is perhaps the toughest soldering job of the bunch, as it required individually soldering each contact of a custom ribbon cable to the CPU on the board. That ribbon cable itself had passive components like a capacitor and, of course, the microSD card slot soldered onto it before.
Now that the Game & Watch had external storage, Macho Nacho put everything back together, performing the final soldering on the speaker wires to reconnect it, but there was still one thing remaining. The SD card slot needed a cutout on the back shell to ensure it was accessible from the outside.
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Thankfully, the modding community already had 3D-printable jigs ready for our host. He used them to drill out the slot, sand it to ensure it doesn't look too DIY, and finally close the Game & Watch back up. At this point, both the hardware and software should be ready (if you prepped the SD card already), and you only need the games.
It's easy enough to dump ROMs on the card, so Macho Nacho spent the rest of the video showcasing what this modded Game & Watch can do. It runs Retro-Go, a popular firmware that has lots of support in the community and features a slick, modern UI. The biggest benefit of Retro-Go is its ability to emulate a bunch of consoles — everything from the Sega Genesis to the Turbo Grafx 16.
The games look beautiful on the sharp display with vivid colors, and the ability to save on the go (save states), thanks to Retro-Go, really adds to the portable nature of the device. Think of it as a DIY Miyoo Mini that you can just put in your pocket and forget. Speaking of which, this Game & Watch is even smaller than a Game Boy Pocket, which it can emulate.
The controls feel responsive, and the device even has Homebrew support. Macho Nacho unfortunately didn't speak on the battery life, but it should be similar to the retail version. The only real con of modding a Game & Watch like this is the sheer expertise involved in performing the mod.
The software side of things can be handled fairly well by tutorials, but microsoldering isn't for everyone. Thankfully, there are people out there who can do this for you, and some who even sell pre-modded Game & Watch consoles. If you don't want the novelty of the form factor, though, you're likely better off buying an Anbernic, which will be more powerful and come ready out of the box.
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usertests I watched some of the video. Was it mentioned what SoC is in there? Like a single-core Cortex-A7 or something?Reply
At about 16 minutes in, it's said to support Game Boy Color, NES, and Sega Genesis. -
Darkhands Somewhere, a Nintendo lawyer woke up screaming and covered in sweat and has no idea why yet.Reply