Could I load its ROM another new code? That's the question!

That was the question back in 2020 - well, to answer this time, yes it works! However it need effort to understand the OneBus, then the ROM dumping process, and finally to recompile the menu with the part of the dumped ROM code that initialises the TFT.

The video: some experimentation with MMC3-mapper games here - it works normally on the handheld. Currently Mapper 0 and MMC3 games worked well. If not mistaken, the ones with MMC1 requires modification of the code (to be compatible to MMC3) which is not covered in this research.

As usual - I'm still in the process of compiling instructions on how to build the custom menu, and also to find a way to build a more economical flasher + dumper so you do not need to use the T56 programmer! :D