expendable sports games

Roni · Post by **Roni** » Wed Nov 05, 2008 1:40 pm

does anyone know which early NES sports games can easily be modded into EPROM (or whatever kind of rewritable chip) devcarts (16/32 kb prg, 8/16 kb chr)? old sports games seem to be the cheapest and most available at pawn shops, bazaars, etc.

also can someone direct me to a tutorial on how to build a mapper 0 devcart?

Roni · Post by **Roni** » Thu Nov 06, 2008 1:50 am

never mind. i guess it's pretty simple. it's just that the pertinent information is all over the place and not so clear, i suppose i'd start by disecting a mapper 0 game and replacing the ICs with sockets...

Jedi QuestMaster · Post by **Jedi QuestMaster** » Thu Nov 06, 2008 12:18 pm

10-Yard Fight is the first game that comes to mind - it's a mapper 0 game, & it's very basic. I wonder why it even was released here - it's not the kind of game I'd see getting people into video games.

Roni · Post by **Roni** » Thu Nov 06, 2008 1:32 pm

better yet is there ANYWHERE i can find a close-to-comprehensive list of games with their respective mappers, or at least a list of mapper 0 games?

Post by **tepples** » Thu Nov 06, 2008 2:24 pm

Boardtable. Enjoy.

Or by "close to comprehensive", were you asking for coverage of games not released in North America?

clueless · Post by **clueless** » Thu Nov 06, 2008 3:32 pm

What does the "RR" column mean in the "board table"?

Side note: It would be nice to have a list of games using a particular board, as part of the wiki pages that detail the specifics of each board type.

ie, http://nesdevwiki.org/wiki/TKROM could list "Crystalis".

Is there a way to cross-load this data from the text file into the wiki (so that the pages would not have to be manually edited)?

Is this a good idea at all?

MottZilla · Post by **MottZilla** » Thu Nov 06, 2008 3:55 pm

You could buy a reproduction board from www.retrousb.com which is already intended for EPROM or FlashROM chips. It's more flexible though probably costs more than if you just rape a cheap game for its pcb.

Post by **tepples** » Thu Nov 06, 2008 4:01 pm

clueless wrote:What does the "RR" column mean in the "board table"?

Rarity. For instance, compare the two versions of Tetris.

Roni · Post by **Roni** » Thu Nov 06, 2008 11:03 pm

it's just what i need. thanks. now i know not to crack open a copy of Ms. Pac Man or Donkey Kong Jr. Math, if i were lucky enough to be dealt one.

how do i know if a FlashROM chip is compatible with the NROMs? does it have some similar insignia, besides pin count?

albailey · Post by **albailey** » Fri Nov 07, 2008 11:16 am

I'd also suggest Bootgod's site

http://bootgod.dyndns.org:7777/

You'll notice that 10 Yard Fight is NROM-256 (because the PRG is 32K I assume) so it is ideal.
On the other hand, Baseball is an NROM game but only has a 16K PRG and is available as NROM-128 so you probably would not want to use it since you might need to do extra work to make use of it for many NROM games.

I kept some info in a word document on doing repros. Here's some info I have on NROM.

EPROM Info
NROM consist usually of a single 16KB or 32KB PRG chip and an 8KB CHR. These are 28 pin sockets, and should not require any rewiring. There is mirroring.

A 32 KB (which is a 256 Kb) chip is fine. The following chips can be added without any additional modifications or re-wiring:
27C256 (EPROM). : http://jameco.com/wcsstore/Jameco/Produ ... /39714.pdf
AT29C256 (Flash) : http://www.atmel.com/dyn/resources/prod ... oc0046.pdf

Modifications required:
NONE. The 27C256 (29F256) chips are essentially identical to the chips that are already on the board.

Hardware Steps:
1. De-solder the PRG and CHR chips from the donor cartridge. This is the step that will give you the most difficulty. You may damage the board, lift the traces, etc..
2. Repair anything you ruined while de-soldering. (A silver pencil can be used)
3. Since no modifications are required, just solder in two 28 pin sockets (one for the CHR and one for the PRG)
4. If mirroring needs to be switched, de-solder the H or V solder bulb on the board, and re-solder the other. (For vertical mirroring, the solder bulb should be the H). Alternatively a switch could be installed (beyond my expertise)

That should be it. Be sure to test it, and if it doesn’t work, use a Multi-meter and try to figure out if there are any shorts, or damaged connections.

Make sure the chip is full. Dont write 16K to a 32K chip. Double up the data and write all 32K.

Al

Roni · Post by **Roni** » Fri Nov 07, 2008 11:28 pm

can desoldering of the IC be done with braid? i guess the chip would suffer in the desoldering process, otherwise i wouldn't mind just pulling the chips out of one of my existing games and popping it back into the socket when i wanted to play it = )

the socket wouldn't cause clearance problems with the insertion of the cartridge, would it?

BMF54123 · Post by **BMF54123** » Mon Nov 10, 2008 1:14 am

I personally use a desoldering iron; it's a soldering iron with a hollow tip and rubber suction bulb attached. You just squeeze the bulb, place the tip over a pin for a moment, and release. No damage, no mess.

I'm pretty sure you can still find them at Radio Shack.

Post by **Memblers** » Mon Nov 10, 2008 3:37 pm

Yeah you need suction, braid will leave a little bit behind (which is more than enough to keep it firmly in there).

Also a perhaps counter-intuitive tip is that sometimes you need to add more solder, to remove all the solder.