I realize this's going to be one mother of a difficult rom hack. Here's what I accomplished so far.
I really like the m5 / m7 bootleg hacks of street fighter 2 champion edition. They're great hacks that're a lot of fun but unfortunately they were released on bootleg pcbs which don't 100% work like an official CPS1. Luckily....the hardware works almost the same.
First I took a look at the m5 / m7 roms in a hex editor and compared them to regular champion edition rom dumps. The roms had been split into two files in an interleaved pattern. I found a tool on the internet and interleaved the roms back together and split them so they were just like the champion edition roms. These rebuilt roms actually do run. I tested these roms in both an emulator AND on eproms on my cps1 board and they run on both, however there's some programming that needs changing.
I dug around in the cps1.c file from mame and it turns out that the m5 / m7 pcb draws sprites in reverse order. Therefore in an emulator when it runs in a regular cps1 profile the sprites are constantly flickering. On my cps1 pcb the sprites barely ever show up but when they do they're flickering just like the emulator. Also the m5 / m7 bootleg pcb has the control inputs programmed differently so on my real cps1 pressing controller buttons did nothing.
I've been trying my best to use the mame debug mode but I'm terrible with this sort of thing. I need to find the code that tells it what order to draw the sprites in and change it to draw them in the same direction as a cps1. Once that's done then we'd just need to change the controller input programming to regular cps1 standards. The controller input code could probably be found just by finding the controller input code in the champion edition roms and copy and pasting that. I would assume setting the mame debug mode to freeze when you press a button would do the trick with finding the programming for that.
If anyone is interested in helping I'll happily send you the m5 roms in the state they are right now which is basically the same as the champion edition rom dumps just with the hack programming inserted. I'm really going to need help finding this programming and applying the changes.
March 18, 2012, 04:12:06 pm - (Auto Merged - Double Posts are not allowed before 7 days.)
I'm proud to announce that this project is 100% done. Here's what I did. Since the champion edition rom dumps and the m5 cleaned up dump are very similar I tried copying data back and forth between the two rom sets and seeing what effect it would have. I did a LOT of trial and error and eventually found the programming that applies all the game hacks while keeping the cps1 compatible programming in tact. The M5 bootleg romset now runs 100% flawlessly on my official cps1 pcb.
Here's the rom zip:Mod Edit: Please don't post ROMs.
If you rename this zip sf2ce.zip winkawaks will run it fine and I assume other cps1 emulators will run it too. To upgrade your champion edition, turbo, or rainbow edition to this m5 hack just burn the 21, 22 and 23 roms and it should run fine on your regular cps1 arcade pcb. The 21 rom is just the regular champion edition rom and the 22 / 23 roms are the hacked up m5 roms.
Here's the video to prove it works:http://www.youtube.com/v/u0o7HeFbGb0