Puzzle Bobble MVS to Home Format Neo Geo Conversion Project

Posted on August 24, 2002

Written by Tiptonium

Puzzle Bobble

I started this project back in June. It seemed simple enough. Samurai Shodown 2 seemed to make the best sense as it would make an excellent host for the arcade MVS version of Puzzle Bobble. But you know what good sense does if you don't use it, right?

It was pointed out to me that I could use a lesser host cartridge. Doing so would require a bit of hackery as wire jumpers and a couple of trace cuts would be required. I thought about doing that sort of job as I had a really scuffed up Fatal Fury 2 home cartridge that I could use. Looking inside of that cart was a disastrous affair. After a visual and tactile inspection I decided to leave that poor cartridge alone. The circuit boards felt sticky and a few of the traces looked like they were ready to flake off! Poor fella, it looks like previous owner did some bad things to that thing. I thought about using a different cartridge but then thought of cutting into the board seemed too extreme for such a project.

The sacrificial host cartridge for this project is Samurai Shodown 2.

After I had stripped the MVS Puzzle Bobble clean of its V, S, C and M chips, it was pointed out to me that there are Power Spike II chips on the boards and indeed they were. Apparentely, original Puzzle Bobbles share this trait and one other... there is an eprom used for the P chip and one used for the M chip. Since decided to do a straight up chip swap, jumper only conversion I needed to move those too. I wonder what the history behind this is? Anyway. I put the whole project on hold until a week or so ago. This would cause me difficulty as I became a little too confident/sloppy in my approach.

I did the soldering work at my garage workbench. To say it has been hot here in Virginia this summer is an understatement. Since it was hot, I rushed the work. I made a couple really bad solder marks tacking down two of the jumpers. It is cosmetic but still, I generally do a good job here. But what really cost me time was when I swapped the two Puzzle Bobble V chips. You see, they do not conform to the normal numbering and lettering sequence. I had put a piece of tape on them back in June to identify them but I paid them little attention when I did the job. Basically, I got them reversed causing the in-game sound effects to go nutz. I used a lifeline in the name of Jeff Kurtz who saw my error in a picture I sent him. Swapping the chips corrected the problem. To make this goof even worse I had taken shot of the MVS boards before starting the project for reference and then I did not even refer to them. Had I done that I would have saved myself a bunch of time not to mention having to get Jeff involved.

Note: It has been pointed out to me by hpman, a cool guy in the know regarding the Neo Geo technical stuff, that Puzzle Bobble is actually 26 MEGS, not 32 MEGS.

Dialing in the CHAR256 B graphics was a bit of a chore. Through trial and error I got the game's graphics to display properly. These settings work, that's all I can say. :-)

Here's my finished project:

Click Here To See Insert...              Click Here To See Label...

That's all for now...  stay tuned!