GPIO Assist - Ultra
The GPIO Assist boards are designed to simplify the process of wiring a Game Boy Zero while minimizing the amount of space required inside the build. They can also significantly reduce the cost and time it takes to assemble your device. The board sits flush against the back of the Pi Zero W. If you position the board so that the Micro SD slot faces the Contrast port, the wires connecting the button board only need to be about an inch long.
The Ultra GPIO Assist board enables the easiest wiring solution compared to the Basic or Pro boards due to the inclusion of power, USB, analog and audio components. Like the other GPIO Assist boards, the Ultra board supports both composite and SPI screens. It also utilizes the same USB and C-Media 102S+ components. The power circuit incorporates a LiPo charger, 5V boost, safe shutdown, power switch, barrel connector and battery monitor via an ADS1015 chip. The board also provides an external USB port and volume control wheel.
Note that you'll likely need to trim the power switch to the appropriate height.
Setting up GPIO Controls using Retrogame
Configuring USB Audio
Configuring Safe Shutdown and Battery Monitoring