The Game Boy DS Lite was one of Nintendo’s most popular handheld game consoles, but unbeknownst to everyone, it has a hidden feature that could have made it even more popular. Exploring the DS Lite hardware and firmware, the [Lost Nintendo History] team found that the System-on-Chip (SoC) in the Game Boy DS Lite can produce a composite video signal.
The SoC can produce a 10-bit digital output running at 16.7 MHz, but it is disabled by the standard firmware at the beginning of the boot process, so a custom firmware was required. It still needs to be converted to an analog signal, so a small adapter card with a DAC (digital-to-analog converter) and op-amp is connected to the top screen’s flexible cable. A set of buttons on the board allows you to select which screen will be displayed on the TV. The adapter card is open source and Gerbers and schematics are available on GitHub.
The current version of the adapter card deactivates the top screen, but the [Lost Nintendo History] the team is considering designing a passageway to eliminate this disadvantage. The TV-out mod can also be combined with the popular Macro mod, in which the upper screen is removed to transform it into a Game Boy Advance. The Nintendo DS is a popular topic about hackers, and we’ve been covering it for over a decade.