Saturn Cartdev MIDI interface module

Discussion in 'Sega Saturn Programming and Development' started by jollyroger, Jan 23, 2019.

  1. jollyroger

    jollyroger Gutsy Member

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    Everyone,

    Ages ago, while studying the Saturn sound system, I noticed (without paying too much attention) that the CartDev system could be equipped with a MIDI interface module to allow composers to use the SCSP as a MIDI target and work on music directly on the CardDev rather than the Sound Box.

    Even though I worked on the Saturn back in the day, I had never actually seen the MIDI interface module, until today.
    There is a picture of it on an auction on Yahoo Auctions Japan right now: https://page.auctions.yahoo.co.jp/jp/auction/k363747446

    While I have no use for it, it would be interesting to reproduce the PCB for preservation sake (I don't think there are many of these around), as it seems to be a rather simple design.

    Thoughts?

    Jollyroger
     
  2. TriMesh

    TriMesh Site Supporter 2013-2017

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    I'm pretty sure it's simply a 20mA current loop interface and it plugged into the serial port on the back of the Saturn.
     
  3. jollyroger

    jollyroger Gutsy Member

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    Well, as you know the CartDev has two cables sticking out directly from the chassis: one is the NMI cable, the second has a small round DIN connector, which is what plugs into this MIDI interface module.
    This should actually be connected directly to the SCSP MIDI interface pins, which are also present on the communication port.
     
  4. XL2

    XL2 Rising Member

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    I see that it has the graphic tools from late 1996 (if I'm not mistaken).
    Any chances it could have some not yet leaked Sega libraries, like something above SGL 3.02?
     
  5. jollyroger

    jollyroger Gutsy Member

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    Hard to tell...
     
  6. jollyroger

    jollyroger Gutsy Member

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  7. XL2

    XL2 Rising Member

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    Yes, it seems like we already have the 3d editor v.3.72, but this one here is 3.71, so it's likely not the lastest pack sadly. I find it a bit hard to believe that Sega didn't update any of their libraries/apps in 1997, but all we have goes up to 1996 if I'm not mistaken.
     
  8. jollyroger

    jollyroger Gutsy Member

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    They may have updated their tools/SDK in 1997, yes, but as far as I know the latest material that was leaked is from late (November) 1996.
     
  9. TriMesh

    TriMesh Site Supporter 2013-2017

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    I'm sure I've seen that board (or one that was extremely like it) plugged directly into the communication interface port on the back of the Saturn. The only cables I can remember going between the CartDev and the console were the ribbon cable for the board that plugged into the cart slot and the NMI cable for debugging - but admittedly this was all a long time ago...
     
  10. jollyroger

    jollyroger Gutsy Member

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    Check out the pictures here:
    https://blogs.yahoo.co.jp/rig_veda/GALLERY/show_image.html?id=59992467&no=2
    https://blogs.yahoo.co.jp/rig_veda/GALLERY/show_image.html?id=59992467&no=7

    As you can see it has a cable coming out of the back, which is not the NMI cable.
    The Cross Saturn in my CartDev system is the same as that one, not all of them were configured this way.
    Some have a flat NMI cable coming out from the front center section, while others have a round cable from the front left section.
    Some have this (MIDI?) cable and some don't...
     
  11. TriMesh

    TriMesh Site Supporter 2013-2017

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    Yeah, I guess it could be a cable for the MIDI interface - the only way to tell for sure is to find out where it's connected to inside the console.

    The interface board in that auction photo is clearly just an opto for the input side and a 7405 (hex inverter with open collector outputs) for the output side - which would make perfect sense if it's interfacing with the TTL level signals out of the SCSP.
     
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  12. jollyroger

    jollyroger Gutsy Member

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    Next time I have mine out of the boxes I will open it up and post a picture of where the cable is connected to...
     
  13. HI_Ricky

    HI_Ricky Intrepid Member

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    any updates ?

    IMG_7414a.jpg
     
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  14. jollyroger

    jollyroger Gutsy Member

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    Oh, I forgot. I have the kit with me now, I will try to get it out and take some pictures tomorrow.
     
  15. jollyroger

    jollyroger Gutsy Member

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    Actually, given that you clearly have a number of CartDev systems lying around, can you open one up and check yourself?
     
  16. HI_Ricky

    HI_Ricky Intrepid Member

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    my saturn dev have special label between top and button case, I don't want bocken it. :(
     
  17. jollyroger

    jollyroger Gutsy Member

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    Ok, I will try to open mine when I have some time.
     
  18. Jackhead

    Jackhead Site Soldier

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    i bought the cartdev setup from yahoo.jp with the midi interface and software. Will also have a look for the connection if Jollyroger found no time to do it.
     
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  19. jollyroger

    jollyroger Gutsy Member

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    Please do, I am swamped, but I would like to know where the MIDI cable is connected.
    The SCSP has direct serial/MIDI lines, so I would assume that is where the cable connects to...
     

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