Why are VBA8 cheats not working?

[Symbian96]

I downloaded a game boy emulator by WP8Emu, that app works great but not the cheats. i have a game called yugioh ultimate master world championship tournament 2006, i used to play it all the time as a kid. i tried activating cheats but they dont work. ive searched everywhere but no solution, please help.

 

[Harrie-S]

Because they are cheats?
There is a difference between an emulator and the real Gameboy and this is probably one of them.