Sega JVS to Jamma I/O (838-13683-93) 6-Button With Blast City

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    • Sega JVS to Jamma I/O (838-13683-93) 6-Button With Blast City

      With the Sega JVS to Jamma I/O, has anyone been able to output buttons 1-3 on Jamma and 4-6 over the kick harness?

      And specifically for people using the Sega I/O with their Blast City, can you really transmit kick buttons through CN6? Looking at Arcade Otaku it appears the the Aux/Kick AMP UP connector is only connected to CN8.


      BACKGROUND
      Currently I’ve been using a Capcom I/O board with my Blast City which is working well. But since it’s the only I/O board I have I’m not able to use my JVS games on my supergun.

      So with that in mind I thought I would save a little money and buy a Sega I/O board instead of a Capcom I/O.

      Looking at the manual I thought it would be perfect. But based some discussions online it appears buttons 1-5 must be output through Jamma.

      I’m actually still waiting for the Sega I/O to come in the mail, so it will take a little time before I will be able to trouble shoot this, but I’m hopeful that someone has run into this problem before.
      fillmoregames.com/pdf/sega_420-6457.pdf
      wiki.arcadeotaku.com/w/Sega_Blast_City_Wiring_Guide
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      The post was edited 1 time, last by landstander ().

    • Finally received the Sega JVS to Jamma converter yesterday, and spent some time trying any configuration I could think of.
      Sadly I couldn’t send buttons 4 and 5 through CN3 on the JVS to Jamma board. And I can only assume that the instruction manual for the Rev B board are incorrect.
      I also confirmed that the CN6 pin out on the Blast City is incorrect. I couldn’t send 4, 5 or 6 buttons through CN6. I even tried changing the “function” of the input by jumping pins 9 and 10 as described in Note9 but it didn’t change anything for button inputs.

      So even if you perfectly recreate the setup as described in the JVS to Jamma I/O manual (wiki.arcadeotaku.com/images/9/…VS_conversion_manual_.pdf) buttons 1-5 for players 1 and 2 must be sent through Jamma.
    • I think so? The buttons were connected as shown in the Blast City Control Panel Pinout image on Arcade Otaku (3rd picture in the first post).

      My goal was to use the Aux/Connector (shown in the image) for buttons 4 to 6 so I can keep the standard Capcom button wiring if I want to swap out a JVS system for my CPS2. Now if I want to install my CPS2 into my Blast City I will have to change the wiring of the buttons in the control panel.

      I’m also thinking about splicing the cables so that the button inputs for 4 and 5 will be sent to both the Jamma and kick inputs. But I’m concerned that if I hook up my CPS2, i could be doubling the signal voltage with it trying to use both the kick and Jamma; or the Jamma pins are grounded making the kick harness think the button is always pressed. Ideally the Jamma contacts for buttons 4-5 on the CPS2 would be open. But I have to look into that or simply measure with a multimeter.
    • @tonyt76 Yeah the splicing the 4 & 5 buttons to connect it to both the K/H and Jamma worked for me. While I think it might be a little YMV depending on the PCB. If the PCB uses a kickharness and the Jamma contacts for buttons 4&5 are grounded, those buttons will always read as pressed. But but on my boards with a K/H those contacts are N/C and I haven’t had issues with the CPS2.