Gameboy Color games on an original Gameboy

[jb143]

If there is not "Game Boy Color Only" message, or if you bypass it somehow, then what will likely happen is that the game will still try to play as normal but the graphics will be all screwed up.

The original Game Boy has a "color" pallet that consists of shades of green. If I remember correctly, the Game Boy Color has 16 pallets of 4 colors each. These will still map to an original pallet but obviously display wrong. Some games were made to look good on both and were generally the black cartridges with the notch in them for the switch.

But I suppose you're looking for something along the lines of the programmers putting something special instead of just a "Game Boy Color Only" message.

[TonyTheTiger]

If there is not "Game Boy Color Only" message, or if you bypass it somehow, then what will likely happen is that the game will still try to play as normal but the graphics will be all screwed up.

I dunno. The GBC is actually a better machine than the original GB which makes me think most games would probably just plain not work.

[jb143]

I dunno. The GBC is actually a better machine than the original GB which makes me think most games would probably just plain not work.

It's better in that it's improved upon, but the basic functionality is exactly the same.

I'm going off personal experience with GB/GBC development. It has been a while since I read through the specs though, there may be some cases where it wouldn't work at all but I think for the most part it would just not display correctly.

[TonyTheTiger]

If so then what was the benefit of the GBC exclusive games as opposed to the black carts?

[jb143]

If so then what was the benefit of the GBC exclusive games as opposed to the black carts?

You are locked to a huge constraint if you want to make it look right on the original as well. There is more tile memory on the GBC so you wouldn't be able to utilize that. Again, the original would try to make use of the data, it just wouldn't be able to display it correctly. Also, GBC has a faster processor so the games would run faster on the original, though you could take that into account. I doubt there's anything that could the original to crash but I could be wrong about that. There could be some fancy techniques that some GBC games might be using (like the high color mode or something) that could cause the original GB to actually crash.

[Satoshi_Matrix]

There are four types of GB games:



Gray DMG - These are the oldest, and intended for the original GB hardware. Everything will run these.
Examples: Super Mario Land, Megaman IV, Metroid II, Tetris, etc.


Gray DMG with SGB logo - These are just like the gray DMG, but also offer special 8-color modes when played on a Super GameBoy, but keep in mind the GameBoy Player for GameCube does not support this.
Examples: Donkey Kong '94, Megaman V, Donkey Kong Land 2, King of Fighters '95, etc.


Black GBC - These are early GBC games that offer compatibility with the original GB and GB Pocket (and Light) as well as 8-color modes for Super GameBoy.
Examples: Pokemon Gold & Silver, Zelda Link's Awakening DX, Wario Land 2, Survival Kids, etc.


Clear cased GBC - These are ones that fully use the enhanced GBC hardware and are incompatible with all prior GB hardware including the Super GameBoy. No clear cased GBC game will play on older GB hardware whatsoever except to give an error message telling you that you're an idiot for even trying.
Examples: Metal Gear Solid Ghost Babel, Pokemon Crystal, Megaman Xtreme 2, Shantae, Zelda Oracle Duo, etc.

[SparTonberry]

The Game Boy Color also had more RAM than the original Game Boy. Obviously any game that tried to use the extra RAM would not work on an original Game Boy.

[davidbrit2]

There are four types of GB games:

Gray DMG - These are the oldest, and intended for the original GB hardware. Everything will run these.
Examples: Super Mario Land, Megaman IV, Metroid II, Tetris, etc.

Gray DMG with SGB logo - These are just like the gray DMG, but also offer special 8-color modes when played on a Super GameBoy, but keep in mind the GameBoy Player for GameCube does not support this.
Examples: Donkey Kong '94, Megaman V, Donkey Kong Land 2, King of Fighters '95, etc.

Black GBC - These are early GBC games that offer compatibility with the original GB and GB Pocket (and Light) as well as 8-color modes for Super GameBoy.
Examples: Pokemon Gold & Silver, Zelda Link's Awakening DX, Wario Land 2, Survival Kids, etc.

Clear cased GBC - These are ones that fully use the enhanced GBC hardware and are incompatible with all prior GB hardware including the Super GameBoy. No clear cased GBC game will play on older GB hardware whatsoever except to give an error message telling you that you're an idiot for even trying.
Examples: Metal Gear Solid Ghost Babel, Pokemon Crystal, Megaman Xtreme 2, Shantae, Zelda Oracle Duo, etc.

Yeah, we know all that already. What I want to know is if any GBC-only games have interesting Easter eggs if you put them in a GB Pocket/SGB.

All I've found so far are some amusing images in Yu-Gi-Oh and Monster Rancher Explorer. Nothing super exciting though.

[A Black Falcon]

Interesting pictures there, though of course no released game would allow you to see that kind of thing; games are either dual-mode, or GBC only, you obviously can't see development stuff like that on actual cartridges.

There are four types of GB games:


http://pics.mobygames.com/images/cov...3089982-00.jpg
Gray DMG - These are the oldest, and intended for the original GB hardware. Everything will run these.
Examples: Super Mario Land, Megaman IV, Metroid II, Tetris, etc.

http://static.giantbomb.com/uploads/..._usa_cart.jpeg
Gray DMG with SGB logo - These are just like the gray DMG, but also offer special 8-color modes when played on a Super GameBoy, but keep in mind the GameBoy Player for GameCube does not support this.
Examples: Donkey Kong '94, Megaman V, Donkey Kong Land 2, King of Fighters '95, etc.

http://superflyku.com/2012X/games/IMG_4571.jpg
Black GBC - These are early GBC games that offer compatibility with the original GB and GB Pocket (and Light) as well as 8-color modes for Super GameBoy.
Examples: Pokemon Gold & Silver, Zelda Link's Awakening DX, Wario Land 2, Survival Kids, etc.

http://gamesdbase.com/Media/SYSTEM/N..._Co.,_Ltd..jpg
Clear cased GBC - These are ones that fully use the enhanced GBC hardware and are incompatible with all prior GB hardware including the Super GameBoy. No clear cased GBC game will play on older GB hardware whatsoever except to give an error message telling you that you're an idiot for even trying.
Examples: Metal Gear Solid Ghost Babel, Pokemon Crystal, Megaman Xtreme 2, Shantae, Zelda Oracle Duo, etc.

There are actually five types of GB/GBC games -- there are also black-cart games with Super Game Boy enhancements. Unfortunately, they do not mark this on the cart, so you have to either have the box (the SGB enhancements are usually listed there; only the US/EU Pokemon games omit the SGB logo, though the support is still there), or look up online/test the games yourself to see which ones have SGB support.

Also, you didn't mention that some early GB games have only the "Game Boy Game Pak" logo in that box, while others, like Tetris there, have a "Game Link" or "Video Link" logo on them. The former is for games which don't support link cable multiplayer; that Game Link, or Video Link for early releases, logo is only on games that support link-cable multiplayer. For SGB-enhanced games, dual-mode games, or color-only, however, you have to look at the box to see if there is link cable support. The four player adapter (it's for the original GB only, there's no GBC 4-player adapter) is only ever listed on the box, not the carts themselves.

[jb143]

Interesting pictures there, though of course no released game would allow you to see that kind of thing; games are either dual-mode, or GBC only, you obviously can't see development stuff like that on actual cartridges.

Yeah, I never got around to adding the GBC only screen...or finishing the game for that matter. Maybe if I ever do I'll add an easter egg for davidbrit2 ;-)

It should be possible to test on actual GBC carts by using a Game Genie but I don't have one for Game Boy.

If anyone else wants to try, the memory address which says which device it's running on is 0143
$80 = is GBC
$00 = GB

By changing the $00 to $80 with a Game Genie, you should be able to trick the program into thinking that the original GB is a GBC.

[Camp]

Lukemorse1 made a video a long time ago that shows a few examples of what happens when you try to run GBC carts in a DMG:

http://www.youtube.com/watch?v=lBekkn9QYFo

[SparTonberry]

Yeah, I never got around to adding the GBC only screen...or finishing the game for that matter. Maybe if I ever do I'll add an easter egg for davidbrit2 ;-)

It should be possible to test on actual GBC carts by using a Game Genie but I don't have one for Game Boy.

If anyone else wants to try, the memory address which says which device it's running on is 0143
$80 = is GBC
$00 = GB

By changing the $00 to $80 with a Game Genie, you should be able to trick the program into thinking that the original GB is a GBC.

I thought the GB model you are playing on was set by the value in A as the boot ROM transfers control to the cart ROM (presumably GB games would store this to RAM later to access it when it needs to check the console used).
Also, 0143 is a ROM address, so I'm fairly sure it can only specify which hardware it was MEANT to run on, not what it is CURRENTLY running on.
Maybe an Action Replay/GameShark (RAM patcher) could be used if you knew which address was used.

[TonyTheTiger]

Yeah, I never got around to adding the GBC only screen...or finishing the game for that matter. Maybe if I ever do I'll add an easter egg for davidbrit2 ;-)

It should be possible to test on actual GBC carts by using a Game Genie but I don't have one for Game Boy.

If anyone else wants to try, the memory address which says which device it's running on is 0143
$80 = is GBC
$00 = GB

By changing the $00 to $80 with a Game Genie, you should be able to trick the program into thinking that the original GB is a GBC.

801-43F-E6A seems to be the Game Genie code for that but it doesn't work. Still getting the warning screen.

[jb143]

801-43F-E6A seems to be the Game Genie code for that but it doesn't work. Still getting the warning screen.

I'd have to look into it a bit more, like I said earlier, it's been several years since I really messed with this stuff. I do remember that there's a register you poll to get what device it's running on, and you use that do decide if you're going to show a "GBC Only" screen, have special shops, or whatever. Another option would be to hack the rom to bypass the startup screen and try it on an emulator.

- Edit
OK, so I found some more tech docs and it looks like SparTonberry was right, 0x143 is programmed on the ROM cart itself to identify what the system it's mean for is. $80 is GBC and $00 is GB.

As for where info is stored that the game uses to tell which system it's running on, that's going to be a bit trickier. That data is stored in the A-register on startup(I'm not sure a game genie can "alter" this and you wouldn't want to anyways).
0x01 = Original GB or Super GB
0xFF = Pocket GB or Super GB 2
0x11 = Color GB
(Also, bit 0 of the B-Register determines if it's a GBC or GBA)

The first thing a program is likely to do is store the value in the A-register in some RAM location, at which point a Game Genie can easily be used...the problem is that each and every game will likely store it in a different location so you would have to look at a ROM dump of the game to figure it out. Not impossible but a bit harder than I was hoping for.