Is there any way to dump/backup a SegaCD RAM cart?

Discussion in 'Dumping and Backing Up Your Games and Prototypes' started by Cyber Akuma, Aug 25, 2018.

  1. Cyber Akuma

    Cyber Akuma Rising Member

    Joined:
    Aug 10, 2017
    Messages:
    54
    Likes Received:
    6
    I know there are devices to read Genesis carts, but I don't know if anyone ever devised a way to backup A SegaCD RAM cartridge, which was basically an external memorycard for SegaCD games.
     
  2. Tommygun

    Tommygun Active Member

    Joined:
    Dec 16, 2008
    Messages:
    35
    Likes Received:
    15
    I did so, but I know of no emulator or system that can make use of the ROM, and generally speaking, there would be nothing to copy unless there was already a game on the cart, as it has no BIOS, just a couple of memory chips on a board. Everything is going on inside the Sega CD programmatically.
     
  3. Cyber Akuma

    Cyber Akuma Rising Member

    Joined:
    Aug 10, 2017
    Messages:
    54
    Likes Received:
    6
    Sorry, I should have clarified. I meant the contents of the cart in order to basically backup/restore the save data on it. Or to transfer it between real hardware and emulators.
     
  4. AUSTIN PEYTON

    AUSTIN PEYTON Gutsy Member

    Joined:
    May 22, 2016
    Messages:
    411
    Likes Received:
    236
    I would be interested in something that could long term save my lunar or popful Mail saves especially since those games are quite long.
     
  5. stevo9389

    stevo9389 Plays It Loud

    Joined:
    Apr 8, 2010
    Messages:
    312
    Likes Received:
    60
    The Mega Everdrive functions just like the RAM cart when you go through the menu to Run CD-ROM. It will save to SD card and you could copy those to PC for long term storage and supposedly rename the extension for use in emulators. I haven't yet explored how to to do it directly from my official Sega cart and Ultra CD Backup.
     
  6. Cyber Akuma

    Cyber Akuma Rising Member

    Joined:
    Aug 10, 2017
    Messages:
    54
    Likes Received:
    6
    I know, I was looking into that as one way, the issue with that though is that it can't read off another SegaCD Ram cart directly, only off the SegaCD's internal memory. So on that of that meaning you would have to copy saves off a RAM cart to the SegaCD's internal memory and back, this would only work for saves that are small enough to fit on the SegaCD's internal memory, some games needed a RAM cart to save because their saves were too big to fit on the internal memory. IIRC, I think one of the Lunar games didn't let you access the last area unless you was saving to a RAM cart instead of internal memory, because the internal memory was too small to save that final area's data.

    I was hoping there would maybe be a way to use one of those cart readers such as a Retrode or Sanni's cart reader to backup/restore the contents of a RAM cart. I was trying to look into possibly adding that feature to Sanni's reader, but I was far too inexperienced both in Arduino programming and electronics in general to even begin to figure it out. I couldn't even find the RAM cart's pinout to tell if it operated at a different voltage or if any pins that were supposed to be data were power or vice-versa that could cause damage to the cart and/or reader.

    That's why I am asking if anyone else ever looked into this.
     
  7. stevo9389

    stevo9389 Plays It Loud

    Joined:
    Apr 8, 2010
    Messages:
    312
    Likes Received:
    60
    I understand that but felt it was necessary to bring up since Austin probably wasn't aware of the functionality. The only "problem" I was made aware of is for the sake of completing Shining Force CD which could be mitigated by just copying those earlier saves off to the Everdrive until needed. I also understand it's a rather expensive solution to the problem so my hopes that someone with the knowledge you're specifically looking for will come forth. He's probably not active here anymore but you can try reaching out to Bad_Ad84 for some ideas.
     
  8. Tommygun

    Tommygun Active Member

    Joined:
    Dec 16, 2008
    Messages:
    35
    Likes Received:
    15
    Ok. There are two solutions:

    1st. Dumping the cart's contents with an Interceptor Mega Disk, like I have.

    2nd. You connect the Sega Genesis + Sega CD through the 2 player port to the computer, and transfer the files via serial modem function of the Genesis controller ports, and I believe you need to burn a cd to run the software. It allows you to load games from your PC to the Sega, and back, since it's purpose is mainly development.

    Here is the diagram for the cable, and links to software to do what you want:

    https://www.retrodev.com/transfer.html
     
  9. Cyber Akuma

    Cyber Akuma Rising Member

    Joined:
    Aug 10, 2017
    Messages:
    54
    Likes Received:
    6
    Hmmm, one thing I noticed is that neither that interceptor nor that serial link program mention they support dumping the contents of the Sega CD RAM cartridge, does it just happen to work because they were tricked into thinking it was a game and dumping it? Or dumping what they assumed was it's save data?
     
  10. Bad_Ad84

    Bad_Ad84 The Tick

    Joined:
    May 26, 2011
    Messages:
    8,619
    Likes Received:
    1,387
    I'd imagine is because the data lines and address lines are the same regardless of if its a cart or ram cart
     
  11. Cyber Akuma

    Cyber Akuma Rising Member

    Joined:
    Aug 10, 2017
    Messages:
    54
    Likes Received:
    6
    Hmm, I wonder if that means Sanni's reader can dump it then since I have one. I was trying to find the pinouts to see if the RAM cartridge was different in a way that could risk damaging the reader before I tried it, but was never able to find info on the poinout of the RAM cart itself.
     
  12. Bad_Ad84

    Bad_Ad84 The Tick

    Joined:
    May 26, 2011
    Messages:
    8,619
    Likes Received:
    1,387
    For the console to access the cart, the address and data lines must be in the same place.

    It should just work in theory. But I wouldnt test it on a cart with data you are not happy to risk - just incase.

    And if it does dump it - its possible it may not split them into files you can use, you may need to hex edit and split each save out. But its a starting point at least.
     
  13. Tommygun

    Tommygun Active Member

    Joined:
    Dec 16, 2008
    Messages:
    35
    Likes Received:
    15
    The reason for this, is because it didn't exist at the time.

    The Specify carts were likely just re-writable game carts, and then when the CD came along, they were re-purposed to be memory cards.

    I'm surprised I can't find anything like it for the 32X.:confused:

    The pin-out is the same for everything that plugs into the Genesis natively.

    It dumps the cart, because it's a development feature, so it will dump anything I stick in there with the right pin-out, including Master system carts, on an adapter. :D

    I don't have a Sega CD, so I can't use the special cable to try, but I'm looking into getting one in the next month, so we'll see what comes between now and then.;)
     
  14. Cyber Akuma

    Cyber Akuma Rising Member

    Joined:
    Aug 10, 2017
    Messages:
    54
    Likes Received:
    6
    Yeah, my issue is really with using the cable on a modern system. While I have very poor soldering skills, wiring up a DB-9 to DB-25 adapter definitely seems like something that would be within my abilities. Issue is, what would I plug that DB-25 adapter into? I do have an old Pentium 3 system with a parallel port.... issue is that it's a desktop on the 2nd floor and the Genesis is in the basement.

    I have no idea if any sort of DB-25 to USB adapter would work, to be honest, I am surprised nobody seems to have done any testing/research on that. I looked up the pinout of a standard DB-9 to DB-25 adapter, and it's pinout was nothing like the one mentioned I had to wire up in the Sega CD link you gave me (I guess that's why they didn't just advise getting a DB-9 to DB-25 cable), this also means that DB-9 to USB adapters would be right out.

    I also assumed that maybe the pinout was similar to that "PC COMMS CARD", the ISA card that EMS produced that was also a DB-25 parallel port, but not pinned like a standard one and worked with their Nintendo/Sony/Sega equipment (I have used such a card in said P3 to backup my Sega Saturn saves through that 4-in-1 Action Replay cart) but I was able to find a diagram of a similar cartridge and it's pinout also appeared to be nothing like the Sega CD cable (Come to think of it, probably safe to assume that EMS used something proprietary rather than an uncommon standard) . So this leads me to assume that his cable design is likely custom made just for his project. Issue is.... this means I have no idea if it would even be possible to find ANY sort of DB-25 to USB adapter so I can use it on modern systems, or even better, on portable ones such as a laptop. It doesn't help that the majority of DB-25 to USB adapters are designed just to work with old printers and are not compatible with any other type of DB-25 device.... or if his PC client would even recognize such a device.

    Not sure if his e-mail is even monitored anymore to ask him or if he is even still active in regards to Sega homebrew anyore, since his contact info mentioned a hotmail account and his AIM handle, and AIM is a service that is now dead, the page was not updated for a while, and the site of the person he mentioned that helped him appears to be dead too.
     
  15. Cyber Akuma

    Cyber Akuma Rising Member

    Joined:
    Aug 10, 2017
    Messages:
    54
    Likes Received:
    6
    Hmm, didn't work. I just tried Sanni's cart reader on a spare cheap SegaCD RAMcart I got. It read it as a 4GB romcart with no sram, and gets stuck dumping it.

    I had asked Sanni before, and he gave me some advice to try to work out adding that functionality myself, however it was far beyond me as I was not even able to find the proper specs to even begin working on it. Which is why I was asking if there was any way to do it. So now I know that Sanni's can't do it natively. Any suggestions?
     
    Tommygun likes this.
  16. Tommygun

    Tommygun Active Member

    Joined:
    Dec 16, 2008
    Messages:
    35
    Likes Received:
    15
    Here is the dump of my Japanese Sega CD RAM Cart.
    I got it used from Tototek.
    The Interceptor Mega Disk says it has a capacity of 16Mb but only had 1Mb of data to copy, so I dumped that as a rom.
     

    Attached Files:

  17. Mord.Fustang

    Mord.Fustang Fiery Member

    Joined:
    Feb 17, 2013
    Messages:
    824
    Likes Received:
    186
    I highly doubt one of those cheap DB25 USB adapters would work. There may be some out there, but the cheap ones will generally only work for printers.
     
    Tommygun likes this.
  18. abveost

    abveost Peppy Member

    Joined:
    Dec 15, 2014
    Messages:
    317
    Likes Received:
    56
    So what did you dump? The first 1M of cart memory? There wouldn't be any save data there. If you could dump the whole 16M addressable by the system you could extract the save data from the correct location.
     
    Tommygun likes this.
  19. Tommygun

    Tommygun Active Member

    Joined:
    Dec 16, 2008
    Messages:
    35
    Likes Received:
    15
    Done.

    **Edit**

    I bought a Sega CD on eBay. :) It will arrive within the next week. :D When it does, I will be able to help you more.;)

    I can setup a memory card dump, and actually be able to tell you, what save game file is contained within the dump, making it a lot easier to know what gets stored in what memory locations, and the organizational pattern it follows.o_O

    The link cable provides this function as well, but I have never tested it, or used it's PC program before, so more learning for me! :eek:

    I'm going to also be exploring the options available, if any, when the Interceptor Mega Disk is also connected to the Genesis. And how well my Sega CD to PC link cable has been wired, since I had no way to know, if maybe, I got the pin-out backwards, for instance. :rolleyes:
     

    Attached Files:

    Last edited: Oct 1, 2018
  20. abveost

    abveost Peppy Member

    Joined:
    Dec 15, 2014
    Messages:
    317
    Likes Received:
    56
    Sorry for the confusion. You'd need to dump 16MByte not 16Mbit. Actually not that much just enough that you read the cart and the RAM which is mapped right after cart space. Either that or start at the address the RAM is mapped to instead of 0 and read 1Mbit. Not sure if the mega disk lets you do that out of the box.
     

Share This Page