I've fixed it already, The ez flash ram connect was dirty and it make the dmg regconized as a GBA card. After cleaning the socket and the EZ jr, every thing solved
So I bought a EZ Flash Jr today and got it home. When I put it in my Gameboy DMG_01, it won't boot. Just show up the nintendo logo (perfect no glitching) and then a emty screen with no sign of boot. I've try many times and also dust cleaning with the card and my device. Then I put the card into...
sorry, beein trying to find this file that's been right in front of me for a month now, only to find broken links, and google to prove that it's completely worthless.