Originally published at: RetroTINK 4K firmware v1.21.0 adds user-defined modelines via SD card | POCG
Mike Chi released experimental firmware v1.21.0 for both RetroTINK 4K models today, and the headline feature is modeline management via the SD card. Previously, the RT4K allowed four custom modeline slots. The new firmware makes slots 3 and 4 user-definable, letting you load a modeline file directly from a /modelines folder on the SD card…