Why does the GBC have an 8MHz crystal?

[Jewjo]

All the other Gameboys have 4MHz. I went to overclock my newly frontlit GBC (with an 8.19MHz crystal) and I couldn't get it to work. After trying for about 5 more minutes, I looked at the preinstalled crystal. "8.3"--I was underclocking the thing!

Well, this topic is just for me to rant. Is there a reason for the 8.3MHz crystal in the GBC and the 4.xxMHz in the SP? I was going to steal the crystal from my spare SP figuring that it would be higher. Argh.

 

[Bibin]

The GBC is twice as fast! It's another change from the old MGB and DMG architecture.

 

[bentendo64]

where did you find an 8.19MHz crystal?
i cant find one any where!!

 

[themadhacker]

I found one in an old cd drive.

They are not that hard to come by. just look around.

 

[eurddrue]

No games ever actually took advantage of the extra crystal thing so they changed it back for the GBA. iirc.

 

[jleemero]

No games ever actually took advantage of the extra crystal thing so they changed it back for the GBA. iirc.

Wrong.

 

[Bibin]

So wrong.

 

[Twilight Wolf]

Oh, yes, I love when people are unhelpful enough to tell me I'm wrong and then don't bother with an explanation. :/

 

[Bibin]

The GBA derives its speed from a multiplier. The GBA architecture is 100% different from the CGB one, so a reason like Eurddrue's makes no sense.

 

[Twilight Wolf]

Now that's more like it. Thank you, I was curious about this myself.

 

[eurddrue]

No games ever actually took advantage of the extra crystal thing so they changed it back for the GBA. iirc.

Wrong.

I asked you this question and that is the answer you gave me.
You said:
CGB=2x the DMG
GameBoy Advance=many times the DMG

 

[Bibin]

Every game that runs with color in it at all? It's using the double clock speed.

 

[jleemero]

Every game that runs with color in it at all? It's using the double clock speed.

What? No no no no no, Bibin I am disappointed in you.

Any Gameboy game could run on a CGB.
With the CGB, many games added color support. Many even before the CGB was actually released.
A simple check to see if a CGB was being used. If it was, enable the colors. If not, then simply don't.
The Double Speed Mode was not required to be used for colors.

Many, games took advantage of the MBC5 Bank controller, which was necessary to run at the Double Speed Mode.
MBC5 Games could still be used on a Gameboy, if they were made to, but of course, it would be impossible to use the Double Speed Mode while being played on a normal Gameboy.
Commonly, "High Color" images were displayed with the help of the Double Speed Mode.
While each Background Tile could only use 4 colors, some fancy ASM that worked as the Tiles were drawn could allow about 2000 colors to be used at once.
(Though, no more than 80 colors per scanline)
It's about the easiest way to identify a game using the Double Speed Mode, looking for highly-detailed images.

 

[eurddrue]

Now it makes sense! Thank you Jlee <3!