Has anyone been able to get Donkey Kong 2 to run?

[mhartman]

The roms are there (dkongx.zip) and it works in hbmame on the pc, but I haven’t been able to get it to work on MiSTer. I tried making an .mra but it freezes on me at the opening sound. Any suggestions? I think it might be because the original required an add on board, which might require a new/altered DK core for mister.

[gamesfan]

I have also tried and failed at editing an MRA to include the extra chip for Donkey Kong II : Jumpman returns.
However I will admit I really dont know much about it, I pulled up the mame driver info..
What I thought was interesting is many MRA for Dkong , including other hacks specify the same rom twice. Which I dont get.

[Gehstock]

there is some Encryption on the Braze Board

[gamesfan]

Interesting, I know in some CPS2 MRA files there is a “key”, do you think in the mame driver the key is specified?

[mhartman]

The roms work fine in HBMAME and MAME, so I’m thinking that the roms are decrypted, but I’m not sure of that.

[gamesfan]

I know mame uses encrypted roms, not sure if all of them are but at least when we add neogeo games they can’t be mame roms they need to be the decrypted ones.

[zakk4223]

It's not 'real' encryption. It's just some bit shifting/swapping. There's no key or anything like that. The mame driver comments say it appears to just be a 'coincidence of easy pcb design'.

I'm not sure modifying the rom to 'decrypt' it will work. The Braze board also has a pal/gal that toggles the A15 line on the Z80, which if I'm skimming the mame driver source correctly modifies where certain memory reads actually read from. Looks like writes to a certain memory address cause the pal to toggle a15, which in turn will cause different parts of the braze rom to be read. I think the core would have to add support for this for it to work.

[pgimeno]

People often think that bit reorganization of address or data lines has to do with encryption. Maybe in some case, but most commonly it has to do with simplifying the PCB. For example, the Shadow of the Unicorn PCB was single sided and didn't have a single bridge, something that wouldn't have been possible had the address and data lines corresponded to conventional order. https://mocagh.org/miscgame/shadowunico ... inside.jpg