I know it may not fit this section entirely, but bare with me.. I am working on a little project which involves coding to the NDS, accessing EZ-flash 3in1. I made a bit of research and found the 3in1 source: 3in1 source I read the source, most of it makes sense, but parts of it seems random, especially when to write to WAIT_CR (enable GBA-port??), and when to use ARM_7 or ARM_9. Specifically i want make the EZ-flash rumble when i want to. My question is, would it be possible to successfully code some GBA-homebrew that writes to the rumble-addresses, or is the GBA-address-scope different in GBA-mode from NDS-mode?