GB on GBA

That's cuz GBA emu's do not 'emulate' gba games the same way a GBA does. If an emu runs games just like the real thing then it will request a bios file as a mandatory addition, which of course is illegal. VBA does not run GBA games like a real gba would (after all a real gba does not have all those spiffy gfx filters) and VB does not run GB games like a GB would. All forgotten did was take what he had for his VB core and integrate it into VBA thus allowing boths systems to work off of 1 emu.

*note to people smarter then me* At least I think that's what the differance is, I don't code these things, I just put um through hell and consistantly bug the authors so I might (read most likley am) wrong.

the cartridges are different. theres a voltage difference, where gb is 5v and gba are 3.8 iirc..
if you had a gba you could look and see that the cartridges are physically different also (im not referring to just the size). theres a switch which is only activated with gb/gbc carts -- the gba carts have a notch that doesnt hit it. there is also a gbc chip incorporated into the gba. so the gba actually switches to a gbc mode when this switch is hit.. its all hardware regulated, nothing to do with the gba architecture itself..

Ah, so there's a switch there to change between systems... hmm, that's more than clear now. As I don't have a GBA (I have glanced at it in my hands, but I didn't notice everthing about it physically), I couldn't tell. I just read it all the time that it actually runs GB and GBC games, so I thought.

>Vagrant
That was my guess... I mean, this emu's system is not a single code for both consoles. Forgotten took separately the code for GBA and GB, and then put it together in only one emu, just like a multiple emu system. At least THIS guess was right (I think).