Few weeks? Try the end of the year :p
I still have to roll through GBC emulation (which really isn't that hard) before I start working on GBA emulation. Right now I'm only doing preliminary work on emulating its ARM CPU. The goal is to finish GB/GBC emulation, then move onto the GBA, and eventually the DS, but that's over a couple of years. Still, it's not like I won't give it a try, if not now then in the future.
I still have to roll through GBC emulation (which really isn't that hard) before I start working on GBA emulation. Right now I'm only doing preliminary work on emulating its ARM CPU. The goal is to finish GB/GBC emulation, then move onto the GBA, and eventually the DS, but that's over a couple of years. Still, it's not like I won't give it a try, if not now then in the future.