Question about donor carts

So I'm buying donor carts for a SMB2J repro, and all of the ones from the cartdb that say they are mmc3, and have the correct size chips on board, don't after I buy them. 



They say they are supposed to be 32 pin boards, but they are all 28. 



Can someone please explain how to use that website to get the ACTUAL carts I need for repros? Cause either I'm really stupid, or the website is consistenly wrong in its searches.



The board types are right, but I need to make sure the games that return in the searches have the correct sized chip slots for what I'm doing. And nothing in the search criteria seems to match.

Comments

  • TLROM, TSROM, TKROM all have 32 holes for the prg and chr chip. games that have 128K (1mbit) of prg data have 28 pin mask roms, but there are still 32 holes on the board.



    and just fyi, not all mmc3 boards are equal. TSROM has a ram chip that TLROM does not, and some games require that to operate. TKROM is configured for a battery where the others are not. beyond that, tlrom boards are pretty small and you have less space to run jumper wires.
  • For SMB2J I believe you'll need a copy of SMB2 that has all contacts on the bottom like the one here: http://bootgod.dyndns.org:7777/profile.php?id=130.

  • Originally posted by: Moothead2



    For SMB2J I believe you'll need a copy of SMB2 that has all contacts on the bottom like the one here: http://bootgod.dyndns.org:7777/profile.php?id=130.





    you're thinking of final fantasy 3. smb2j should be fine without those pins.
  • Ah yes, my bad. Always seem to get those two mixed up for some reason.
  • Interesting. I've opened 4 different TLROM boards, and all of them only have 28 pins for both PGR and CHR.

  • Originally posted by: Kuros



    Interesting. I've opened 4 different TLROM boards, and all of them only have 28 pins for both PGR and CHR.





    what games? that sounds like TEROM or something instead of TLROM
  • Yeah that doesn't sound right, I thought initially I had run into this problem before but retracing bootgod's list I can't cite example for a CHR with less than 32pins on a TLROM.



    Are you sure you're looking at the proper revision of the board if you're using bootgod's DB? A few games have different board revisions like Gauntlet.
  • http://bootgod.dyndns.org:7777/profile.php?id=639



    For instance. Should be a 32 pin TLROM.

    It's not. LOL
  • No, it's 128KB. Nintendo used a custom ROM with a pin killed for the extra data line, only 256KB PRG-ROMS will have 32-pin.



    http://bootgod.dyndns.org:7777/profile.php?id=272



    (Used for reference instead because it has an actual PCB picture.)
  • I can verify this as I just scraped a copy of 8 eyes the other day for Ufouria.



    As much as I love the Bootgod DB you need to be careful. Sometimes it's just not accurate or you aren't seeing the proprietary board design on the profile. In your searches go to PCB/Hardware and set the board type to NES-TLROM and mapper to 4, go to the games tab and set the release country to your country of origin and that should do it. Just always look so see if there's a pic on the DB first, sometimes I think they're going by rom header info instead of verifying each and every cart.



    When in doubt check the hardware section of the profile to ensure the mask roms are 32 DIP. If it doesn't say that, don't use it unless you have it laying around to verify it yourself.

  • Originally posted by: Kuros



    http://bootgod.dyndns.org:7777/profile.php?id=639



    For instance. Should be a 32 pin TLROM.

    It's not. LOL



    Does your cart have a konami board? If so can you post a pic?



    For the Nintendo made boards you can see the 28 pin mask prg with the extra 4 holes. Look at the other profile here:



    http://bootgod.dyndns.org:7777/profile.php?id=901



    The konami boards may only have 28 holes for the prg- that's how their version of unrom is laid out. For the unrom version you hang pins 1,2,31,32 out over the edge and just wire as necessary.


  • ^ I missed that, great point! Konami loved to use their own boards because Nintendo let them.
  • Here's the pic of the Top Gun Second Mission board.



    http://i.imgur.com/Z4TU5.jpg
  • Yeah, that's a custom board with even custom ROM chips. I forget really what Konami games use but as I understand that take standard EPROMS sometimes. I'm not sure the situation and if that would though, I doubt it.



    ETA: Seems to be a board also set up to be used with CHR-RAM also, nice. And you can almost tell it's not an official Nintendo board because even though it says Nintendo, it's about 2 years after Nintendo took all the centermost pins off their MMC3 games because they didn't want CHR-RAM use.
  • So is there a trick to using this database to make sure I get the absolute correct one?
  • do your copies of top gun have "24" printed on the back label? for unrom games, that indicates it's built with a konami board.



    you found the right profile in the db the first time. it just happens they didn't have a photo of that version of the board for that game. if you look at super c you can see the photo for that type of board



    http://bootgod.dyndns.org:7777/profile.php?id=128



    and the other profile have photos of the nintendo style board.



    you can use that board as a donor if you want, but it's probably going to be more work that you want.



    konami produced boards use the nintendo 'prg' layout for both prg and chr. since that game has 128KB of data for each, they are going to be 28 pin chips.



    you can put 32 pins eproms in place of those mask roms by putting pin 3 of the eprom in hole 1 on the board. you have to lift the extra legs on the eprom and wire them accordingly. for 128KB eproms it would be



    pin 2 -> hole 22

    pin 24 -> GND

    pin 32 -> +5v



    i don't know what you do in the case of 256KB eproms. these boards may not support that.



    the wiring is pretty straightforward, but it looks like the prg eprom will end up hitting one of the tabs in the cart shell. I've run into that doing punch out hacks and you have to cut part of the tab away.



    for simplicity I would recommend finding an alternate donor for beginner projects. super mario 2 or 3 are sure to work for any tlrom/tsrom game.



    here's some general info about mask roms in nes carts: http://wiki.nesdev.com/w/index.php/Mask_ROM_pinout
  • Our SNES games are built with new boards at http://shop.chipmasters.us
  • Not for sa1 or any other board with a special chip though just hirom lorom and exhirom
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