The credit for this idea has to go to nitro2k01, his genius idea helped me test program my USB Gameboy Camera before i had fitted the USB part. I don’t have a programmer so this was the idea.
Basically i added a switch to my USB cart so that it would disconnect the CE pins from the MBC5 and the flash chip, then using an adapter it can be used to program carts and read/write saves etc, then flicking the switch turns it back into a cartridge.
I wanted the switch to be strong so i used the programming holes in the USB board, but I had to cut the traces first.
I really wanted to use black wire but I had none left, so I used purple to match the LEDs.
The case all together, another crappy hole cut by me.
This is the adapter, its just a back to back cartridge socket.
Here it is reading the save from my Gameboy Camera.