GBA program that enters GBC mode.

[mcdougall57]

i gave it another go and it works fantastically here i come zelda links awakening

[Hypershell]

If you've got a GBM and a flash cart, just use Goomba Color to emulate the GBC games. This program, while interesting, doesn't accomplish too much.

It's true that the program does jack, but it's the concept that's so tantalizing. The reason tapping into the GBM's Z80 is such a big deal is that the GBA is not powerful enough to emulate the Z80 double speed mode properly, which results in Goomba Color slowing down in several games. Finding the ideal switch between Full and Timers mode helps a lot, but it's still not perfect. And according to Dwedit, it never will be so long as it stays on GBA. Which leaves GBM users up the creek on the higher-end GBC games (not that Goomba Color isn't anything short of amazing; the fact that it came as far as it did boggles my mind).

On the other hand, I always saw GBC emulation as being more relevant to the DS (which this program obviously doesn't work on). If anyone after GBM's release wanted GBC games that bad, they should have gotten a backlit SP instead (as in AGS-101, not AGS-001), and saved a few bucks while they were at it.

[DanTheManMS]

I agree, the idea is tantalizing, but it appears that the idea's been given up on for now. Here are a few posts from the PocketHeaven thread you may find interesting:

When you have a GBC game in a GBA, it first boots in GBA mode, then the gba looks to see whether you have a GBC cartridge inside, then boots GBC mode.

Or at least, in theory, this is supposed to happen. However - If it boots in GBA mode, sees that a GBC cartridge is inserted, and does a soft switch to GBC mode, it will do a fade animation before entering GBC mode. The fade animation does not actually happen, so therefore a real GBA never uses a software switch to GBC mode.

I read somewhere (I'll add the link if I figure out where) that the original creator of the GBA attempted to identify GBC cartridges in software mode, but could never make it work. He found no way to use the GBA's 3v inputs to determine when a 5v GBC cartridge was inserted, and rather than risking frying a GBA cart that didn't have proper contact, he elected to implement the hardware switch.

Since he was so reluctant (according to the article) to use a hardware switch, it makes sense that he worked on a software switch for so long that there wasn't time to remove it completely from the BIOS when the GBA shipped. (And that's a pretty long time, seeing as the GBA was developed at about the same time as the GBC, but it was held back not to impede GBC sales.)

Just my $0.02
trlkly