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Author Topic: GameBoy opcode mnemonics, and other stuff i dont get  (Read 14070 times)

MushroomWobbit

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GameBoy opcode mnemonics, and other stuff i dont get
« on: January 04, 2011, 08:22:54 pm »
I'm trying to make my own emulator, just to see if i can.
i found what looks like a GREAT file with the opcodes that the gameboy uses, but im not familiar with any of the mnemonics,
so far all i can assume is that LD is like MOV from what i learned so far in PC assembly, but im not even sure about that.
any chance someone nice here could point me in the direction of a file that explains these, or could maybe tell me about them?

thanks to anyone who could help!
and yes i tried google, and this is the best file i found!

also this is the file i found: http://goldencrystal.free.fr/GBZ80Opcodes.pdf

Ryusui

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MushroomWobbit

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Re: GameBoy opcode mnemonics, and other stuff i dont get
« Reply #2 on: January 04, 2011, 11:17:59 pm »
EDIT:
i just noticed that that sites opcode mnemonics page shows what the codes do if i hover my mouse over them!
thank you very very much, its exactly what i need i think!
« Last Edit: January 04, 2011, 11:31:06 pm by MushroomWobbit »

golden

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Re: GameBoy opcode mnemonics, and other stuff i dont get
« Reply #3 on: January 05, 2011, 06:19:57 am »
You might also find this document useful: Study of the techniques for emulation programming.

KaioShin

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IIMarckus

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Re: GameBoy opcode mnemonics, and other stuff i dont get
« Reply #5 on: January 05, 2011, 07:57:00 pm »
i found what looks like a GREAT file with the opcodes that the gameboy uses, but im not familiar with any of the mnemonics,
so far all i can assume is that LD is like MOV from what i learned so far in PC assembly, but im not even sure about that.
I heard that they (the creators of the Z80) changed all the mnemonics because it was a derivative of the 8080 and Intel claimed copyright on the instruction set.

I use GBCPU_Instr, simply because the name is easy to search for when I forget the link. Some Game Boy resources have incorrect flag results (and so forth) for opcodes, and I don’t know if this is one of the correct ones.

If you really want to be sure, you can check the source code of an existing emulator. The most accurate emulator with source available (in fact, possibly the most accurate bar none) is Gambatte.

MushroomWobbit

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Re: GameBoy opcode mnemonics, and other stuff i dont get
« Reply #6 on: January 07, 2011, 05:30:57 am »
You might also find this document useful: Study of the techniques for emulation programming.
i really like this, and I'm trying to read it now!
i just wish it wasn't written in broken English >.<