nesdev.org

I've seen quite a few projects on this board of people converting the arcade roms to actual carts, and reproductions being made but is there a site anywhere that has conversions done and can be run on emulator or powerpak? Such as a site that has IPS patches for Vs/Playchoice games so that they will run on a NES?

I'm over 90% certain that PlayChoice ROMs will run unmodified, as the NES half of a PlayChoice appears to be just a Famicom Titler whose CPU the hint screen circuit can freeze once coins have run out. In fact, the multicart I made for the Midwest Gaming Classic ran on a modified Contra board, with the ROM and the 7432 replaced.

Vs. Unisystem games would need patching to use the standard palette, standard Zapper, and standard Start button. As for Vs. Dualsystem games that use two NES systems with a block of shared memory, I don't see how they could be ported at all without heavily rewriting them to bit-bang serial communication on the second controller port.

Interesting.

Are there any guides to converting playchoice split roms from the MAME set to a .NES image?

I just tried my hand at it by merging the PRG and CHR and adding a nes header but it did not work correctly:

I've never seen the "MAME version", just a .NES file. But anyway, you forgot to set the header's number of CHR pages, so the game is using CHR-RAM instead of CHR-ROM. FCEUX is showing it's default values for CHR-RAM (horizontal stripes).

Cool, got it. There's actually one extra 8KB file that was in the mame rom set, not quite sure what it contains, perhaps it's still part of the CHR but seperate because it's larger than 128KB so they split it to a separate file. Not really sure what the guys in MAME do. Either way, it needed to be appended after the CHR data and now it runs just fine!

It's the cheat ROM file/screen info.

Pasky wrote:

Punch-out for 2600?

Fceux fills CHR RAM with 00 00 00 00 FF FF FF FF 00 00 00 00 FF FF FF FF by default. It's better than what it used to do: leave it uninitialized from your system ram's contents. Metroid would crash if CHR-RAM was uninitialized.

Metroid would crash if CHR-RAM was uninitialized.

But on real hardware it IS uninitialized !

Like any other SRAM, CHR RAM is initialized from the relative size of the 0 and 1 transistors in each cell. One manufacturing process resulted in the 00000000FFFFFFFF pattern.

I see, but it's only one manufacture process, right ?
Another process might result in something else. Especially considering that normally you'd like both pairs of transistors to have the exact same size (why wouldn't you do this) so it would result in random-like data at powerup.

Found these by a member here;

http://nes.goondocks.se/patches.php

Unfortunately he provides no CRC's of the roms he used to apply the patches and uses .ips which has no method of verifying the rom. Every rom I've tried has failed, tried the VS dump, the mame dump, and even the regular nes rom.

Also this neat patch:

http://www.romhacking.net/hacks/1014/

Pasky wrote:Found these by a member here;

http://nes.goondocks.se/patches.php

Unfortunately he provides no CRC's of the roms he used to apply the patches and uses .ips which has no method of verifying the rom. Every rom I've tried has failed, tried the VS dump, the mame dump, and even the regular nes rom.

Also this neat patch:

http://www.romhacking.net/hacks/1014/

I used all of oRBIT2002's patch and they all worked flawlessly. The only issue I had was with VS Castlevania. He hacked the game the use mapper 2 instead of 99 but the patch doesn't change the mapper # listed in the header of the rom. It's a only a matter of changing the mapper number to 2 using an hex editor, header editor or Nestopia.