What are the original button codes for the earlier Pokemon games?

I know there were once original codes in the earlier games that did not require a Game Shark type device. I've seen a kid type it once for Pokemon Silver, on my GBA. There has to be codes for Blue, Red, Yellow, Silver, Gold, possibly Crystal. But for some reason, you can never find these on the internet. What are the button combination codes, and what do they do? Please help, thanks!|||If you hold down A and B for 10 seconds, you will automatically surrender all your rare Pokemon to team rocket. I suggest you do this as soon as possible.