Gameboy Development Forum

Hi there, I wanted to share my latest work with you.
I've made a GB flashcart based entirely on one chip: an STM32F405 microcontroller. My motivation was to make the cheapest possible flashcart that could run LSDJ.

Of course it turned out using an STM32 for this purpose is not a terribly original idea (https://dhole.github.io/post/gameboy_cartridge_emu_1/), but I went as far as to make it an actual usable cartridge.

Everything seems to be working fine. It should be able to run any GB rom with up to 768KiB of ROM and 128KiB RAM.
It even has USB mass storage for upload and download.
The battery was supposed to help with saving cartridge RAM to microcontroller's flash when you turn off the console, but due to a design error it's useless. Instead, saving is done manually by pressing the button.



Here is some documentation:
https://emeryth.net/stm32-game-boy-cartridge/
https://emeryth.net/2020/01/03/lsdj-on- … cartridge/
Hardware design and code:
https://github.com/Emeryth/stm32gbcart
https://github.com/Emeryth/stm32gbcart-fw