Gamer Turns a Zelda Game & Watch Handheld into a Retro Gaming Beast

Tito of Macho Nacho Productions takes out his trusty screwdriver and goes to work on a limited edition Zelda Game & Watch from Nintendo that he received in 2020. This portable includes three iconic games: the original Legend of Zelda, Zelda II: The Adventure of Link, and Link’s Awakening from the Game Boy. It comes with a great collection of features out of the box, including a crisp LCD screen, a nice D-pad, and separate start and select buttons. The battery life is adequate, and it even has a USB-C charging connection, but Tito wants to take this device to the next level.

First, he removes four screws from the back plate, disconnects the battery, and then pulls out the two ribbon cables that link to the LCD. The speaker desolders, giving him some freedom to operate with. The motherboard is then released by removing ten additional screws. Tito connects an ST-Link programmer to the SWDIO, ground, and SWCLK pads as he boots up his PC and launches PowerShell as an administrator. He utilizes Chocolatey to install Python, Pipix, OpenOCD, and G&W Manager from GitHub. The unlock command is executed, and the device displays a blue screen. Everything appears to be in order.

Tito removes the original 16MB flash chip, which is a bit of a bottleneck, and heats it with a hot air station before applying flux to the pads. Tin foil and Kapton tape protect the area to prevent the neighbors from becoming too hot, and then it comes off clean. He cleans the pads, inserts a new 64MB chip, and reconnects the cables. G&W Manager flashes some custom firmware onto the device, which actually works for a second before halting at step 13. A retry resolves the issue, and Tito resumes business.

The next step is to create a custom ribbon cable by soldering a couple of capacitors, a resistor, and an LDO regulator on. He inserts a microSD card slot and reduces the alignment posts flat. He aligns the ribbon pins with the CPU pads, connects a wire to a capacitor, and then uses a rotary tool to scrape off the soldermask and reveal the ground plane. With a little wire and some work, the microSD slot is fully operational. Tito next tackles the rear shell mods, removing the D-pad posts, drilling four holes with 3D-printed jigs, and smoothing out the edges with a file to ensure everything is nice and flush.

With all of the mod completed, it’s time to launch his own firmware. He downloads the firmware update binary from RetroGo SD on GitHub, places it on a FAT32 microSD card, and turns the device on to install it. Once completed, he restarts it and enters RetroGo – from there, it’s as simple as adding some ROMs for the Game Boy, NES, SEGA Genesis, TurboGrafx-16, and other systems. Super Mario World works well, and Zelda: A Link to the Past is as crisp as ever.