Mappy fans of the world our hopping friend comes to life !!

After a few request for help getting Hopping Mappy running on the Rolling Thunder Namco 'system 86'  game board, and seeing as I'd done the same for Skykid DX I took a look at the hardware & software to see what could be done. Here are the results.. Hopping Mappy on a Rolling Thunder board.

Hardware & Software

The Hardware used for Hopping Mappy is virtually identical to Rolling Thunder PCB.A change of one of the address decoding custom chips stops the upgrade being a straight ROM swap. The Hardware differences are pretty minor, and the same type of patches used with SkyKid DX were all that was needed. 

Some control addresses are modified to new locations. The Interrupt enable/watchdog timer reset are modified on the sound CPU, and the watchdog reset is modified on the sub CPU. Two simple program hacks and the game will happily run on a unmodified Rolling thunder. 

The following is a walk  through of doing the upgrade, the only problems I can see if getting the color PROM's burned. 

The mods process is very, very similar to Skykid DX.

Before you Start 

This conversion hack requires a certain level of technical ability so DO NOT attempt this without the correct tools and some experience in board level repair work.