cosmosiss Posted June 18, 2008 Share Posted June 18, 2008 (edited) I picked up a nice arcade control panel that I intend to use for the 7800/2600. So I open a Proline to check out the wiring and I see there's three components that I need. I could just reuse these, but I'd rather use new parts, and save the old thing from being a victim of cannibalism. So the big question is, what are those three things, and where can I find them? Edited June 23, 2008 by cosmosiss Quote Link to comment Share on other sites More sharing options...
BigO Posted June 18, 2008 Share Posted June 18, 2008 (edited) Two of the things are run-of-the-mill resistors (looks like 620 ohm). By looking, I'd guess the other to be maybe a diode, but I don't know what function it serves. There's a schematic of the 7800 controller here:http://www.atariage.com/2600/faq/?SystemID=2600, (scroll down to the area entitled "Q: What is the 2600 Joystick Pinout information?") but it doesn't show a third component. Edited June 19, 2008 by BigO Quote Link to comment Share on other sites More sharing options...
cosmosiss Posted June 19, 2008 Author Share Posted June 19, 2008 aww common BigO. How about a closeup? Maybe I should just use these to make sure, no? Quote Link to comment Share on other sites More sharing options...
aftermac Posted June 19, 2008 Share Posted June 19, 2008 When I modded my NES gamepad the two resisters were used, but the diode was not. Not sure why. There wasn't any equivalent on the NES board, either. I followed the instructions exactly. You can pick up the resisters cheap at Radio Shack or an equivalent electronics store. I just used the ones from the proline board, because I was never going to use that controller again. Quote Link to comment Share on other sites More sharing options...
Prodos8 Posted June 19, 2008 Share Posted June 19, 2008 (edited) I believe its an inductor??? What ever it is its not needed for the circuit to work as I've made several RSI:7800 sticks & NES:7800 pads without it that work just fine. Yes, the two resistors are 620ohm. Something close to that will work as well. Edited June 19, 2008 by Prodos8 Quote Link to comment Share on other sites More sharing options...
cosmosiss Posted June 19, 2008 Author Share Posted June 19, 2008 So two 620ohm resistors and I'm good to go. Thanx guys Quote Link to comment Share on other sites More sharing options...
BigO Posted June 19, 2008 Share Posted June 19, 2008 (edited) Yep, with the closeup I don't see any of the typical diode markings so I'm gonna go with Prodos8. Might be interesting to see why that inductor is there. An inductor, generally speaking, passes DC and resists passing AC. It would be a filter of some sort, but I'm not sure where the electrical noise would be coming from that they're trying to filter. Can you trace through to determine which pins it connects to at the console end of the cable? (Not worth a lot of your time, I'm just curious.) Two resistors and you should be good to go. Should be about a buck for a pack of 5 of a common value like that at Radio Shack. Just bought some a couple of days ago. If I remember correctly, the resistors are there to make the controller compatible with a 2600. When plugged into a 2600, pin 6 is an output from the controller that acts as the button input to the console. Pushing either button connects pin 6 to ground through one of the resistors which drop little voltage so the 2600 still sees it as a button push. The 2600 button is active low. When plugged into a 7800 pin 6 is fed by the console with +5 volts. The two resistors connecting to pin 8 hold pins 5 and 9 low until a button is pressed thus connecting either pin 5 or pin 9 to + 5 volts, overriding the ground signal supplied through the resistors (aka pull down resistors). The button inputs on a 7800 are active high. Unless the inputs on a 7800 are floating and require the pull down resistors (which I seriously doubt), I think the controller would function perfectly fine on a 7800 without the resistors (no connection to pin 8 would be required). Although, the buttons would then do absolutely nothing on a 2600, you could test your controller on the 7800 without the resistors if you're anxious. Just don't make connections to pin 8 without those resistors. Good luck. Pictures are expected. Edited June 19, 2008 by BigO Quote Link to comment Share on other sites More sharing options...
Prodos8 Posted June 19, 2008 Share Posted June 19, 2008 (edited) I opened up one of my cannibalized prolines to have a look at it and found that its definitely a ferrite inductor of some sort. Its only function seems to jumper the ground connection from the console over to the directionals & buttons. Maybe it filters out circuit noise of some sort, but like I said earlier I've built several 7800 controllers w/o this and haven't had any problems so I'd say its safe to leave out. Edited June 19, 2008 by Prodos8 Quote Link to comment Share on other sites More sharing options...
Shawn Posted June 19, 2008 Share Posted June 19, 2008 So two 620ohm resistors and I'm good to go. Thanx guys yep thats all you need. you can even use a little lower or higher rating zisters too as long as they are the same rating. 600 to near 700 ohms are all fit for 7800 controller use. Quote Link to comment Share on other sites More sharing options...
cosmosiss Posted June 19, 2008 Author Share Posted June 19, 2008 Good news all around then. This shouldn't be too hard to accomplish. I won't have time to work on it for a couple of days, but I'll show off the CP anyways. I think it's safe to say I've reached the point of no return in this hobby. Quote Link to comment Share on other sites More sharing options...
cosmosiss Posted June 23, 2008 Author Share Posted June 23, 2008 OK, I tried three times and didn't get anything. No stick or buttons. Just when I was about to give up, I decided to introduce that inductor thing, and it worked. Perhaps we are looking at Prolines wired differently? Anyways, even if it looks kinda hacky, I'm pretty happy with the results. Couldn't solder the resistors/inductor with the wire, so I just looped the wire and twisted the cables around it. Then I could add some solder to the mix. Not the perfect solution, but it works. Next I will probably build a wooden box for it. More pics: The mess of cables The cluster Organized Quote Link to comment Share on other sites More sharing options...
BigO Posted June 23, 2008 Share Posted June 23, 2008 (edited) It's not that I don't believe you, I just don't understand why it wouldn't work at all without the inductor. I can't quite make it out in the picture, how is it connected in the circuit? I see that one end is tied to the junction of the two resistors (which is ground in the 7800 application), but what is the other end attached to? I have a 7800 controller project I'll do some day so maybe I can learn enough here to avoid problems for myself in the future. (I read what Prodos8 said about it, but that doesn't sync up with my understanding of the 7800 controllers, namely the buttons are active high and jumpering them to ground through an inductor when they're already pulled to ground through resistors just isn't processing in my brain.) I may tear down a controller and see what's up. Edited June 23, 2008 by BigO Quote Link to comment Share on other sites More sharing options...
Jess Ragan Posted June 23, 2008 Share Posted June 23, 2008 You're turning this into an Atari joystick? So does this mean you're going to scrub off the "Licensed by Nintendo" logo on the panel? Quote Link to comment Share on other sites More sharing options...
cosmosiss Posted June 23, 2008 Author Share Posted June 23, 2008 BigO, now that I think about it, at first I didn't use the black wire coming from the joystick cable at all. Was I supposed to go with it to the ground for the stick, simply bypassing the inductor? Boy is my face red. You're turning this into an Atari joystick? So does this mean you're going to scrub off the "Licensed by Nintendo" logo on the panel? Hahah NEVER Quote Link to comment Share on other sites More sharing options...
BigO Posted June 23, 2008 Share Posted June 23, 2008 (edited) BigO, now that I think about it, at first I didn't use the black wire coming from the joystick cable at all. Was I supposed to go with it to the ground for the stick, simply bypassing the inductor? Boy is my face red. I honestly don't know without a little research, but if the black wire connects to pin 8 at the console, then I'd say that was the problem. On the other hand, I'm surprised that the pulldown resistors would be required to make this work with the 7800. I was fairly sure it would work with no resistors if hooked up to a 7800. You are hooking up to a 7800, right? Edited June 23, 2008 by BigO Quote Link to comment Share on other sites More sharing options...
cosmosiss Posted June 23, 2008 Author Share Posted June 23, 2008 (edited) Don't know where the black wire connects to the 7800 port. But you can see in the pic Prodos posted, the inductor goes between the black wire and the directionals ground. The red wire goes to the left button, and after going through a resistor, it connects to that same grond I mentioned above. That's why I thought the black wire wasn't needed. Obviously no expert here. I never did try it without the resistors though. I wanted this to be 2600 compatible so I went straight to business. Edited June 23, 2008 by cosmosiss Quote Link to comment Share on other sites More sharing options...
Almost Rice Posted June 23, 2008 Share Posted June 23, 2008 OK, I tried three times and didn't get anything. No stick or buttons. Just when I was about to give up, I decided to introduce that inductor thing, and it worked. That's weird. I dont have an inductor on my stick. Where does it go? I guess I have to open the prolines I have coming in the mail. Too bad you did not get dual joysticks. Robotron rocks when played with the proper controller. You have the opposite problem I have, 1 joystick but 6 buttons in total. I have 2 sticks and only 2 buttons. I need to find our where I can get a couple of buttons. Quote Link to comment Share on other sites More sharing options...
BigO Posted June 23, 2008 Share Posted June 23, 2008 (edited) Don't know where the black wire connects to the 7800 port. But you can see in the pic Prodos posted, the inductor goes between the black wire and the directionals ground. The red wire goes to the left button, and after going through a resistor, it connects to that same grond I mentioned above. That's why I thought the black wire wasn't needed. Obviously no expert here. I never did try it without the resistors though. I wanted this to be 2600 compatible so I went straight to business. I guess we need to see to it that you get an ohmmeter/continuity tester. [EDIT]: okay, I broke down and opened up a Proline controller. Ground doesn't connect to anything without going through the inductor. Sorry, not sure how to do an ASCII inductor, but here's my best shot at the modified schematic... /----------YLW(-) pin 9 Button L / /---------()---| YLW splits / \----/\/\/-----\ pin 6 ORG(+) -------| ORG splits 520 ohm |---/()()/---BLK(-) pin 8 \ /----/\/\/-----/ \---------()---| 520 ohm Button R \ RED splits \----------RED(-) pin 5 Edited June 23, 2008 by BigO Quote Link to comment Share on other sites More sharing options...
+Mitch Posted June 23, 2008 Share Posted June 23, 2008 Are we sure that it's actually an inductor? I thought I remembered checking it a few years ago and it was just a plain jumper. When I built my custom 7800 sticks I didn't use it. I did use the resistors though. Mitch Quote Link to comment Share on other sites More sharing options...
BigO Posted June 23, 2008 Share Posted June 23, 2008 (edited) Are we sure that it's actually an inductor? I thought I remembered checking it a few years ago and it was just a plain jumper.When I built my custom 7800 sticks I didn't use it. I did use the resistors though. Mitch No, I'm not sure it's an inductor. But, given that: A) an uninsulated piece of wire would work perfectly in the same physical location B) had the trace been left in place for just 1/16" further instead of etching it away there'd be no need for the jumper I'm have to go with the theory that it's not just a jumper. Since it's a relatively clean DC source and there are no relays or back EMF generating coils to protect against pulse to protect against, my guess of a diode doesn't make any sense. I also can't see a benefit of the voltage drop of a diode in that circuit. The outer surface of the device certainly has the look of ferrite. It's a relatively safe bet that it isn't a capacitor (functionally, aside from the fact that it doesn't look like any cap I've ever seen. I dunno, maybe there's some high frequency action happening on the inputs that they thought was feeding back through the ground when a contact was made? Maybe I'll look at it further I was surprised that the fire buttons on the OP's custom controller didn't work at all without that link in place. Edited June 23, 2008 by BigO 1 Quote Link to comment Share on other sites More sharing options...
Almost Rice Posted June 23, 2008 Share Posted June 23, 2008 (edited) /----------YLW(-) pin 9 Button L / /---------()---| YLW splits / \----/\/\/-----\ pin 6 ORG(+) -------| ORG splits 520 ohm |---/()()/---BLK(-) pin 8 \ /----/\/\/-----/ \---------()---| 520 ohm Button R \ RED splits \----------RED(-) pin 5 Are you sure it is not just a jumper on pin 8? Mine is the same except no inductor and 470 ohm resistors. The bottom schematic is what the one I used to do my joystick. Here is my modification of the FAQ for use with SEGA wires # Joystick Pinouts 2600/7800 pinouts: _________________ \ o5 o4 o3 o2 o1/ \ o9 o8 o7 o6 / \___________/ Female pin # 2600 control 7800 control Sega Genesis extension cable 1 WHT- Up WHT- Up Brown 2 BLU- Down BLU- Down Red 3 GRN- Left GRN- Left Orange 4 BRN- Right BRN- Right Yellow 5 unused RED- Button (R)ight (-) Green 6 ORG- Button ORG- Both buttons (+) Blue 7 unused (+5v) unused (+5v) Grey 8 BLK- Ground(-) BLK- Ground(-) Black 9 unused YLW- Button (L)eft (-) White 2600 control (button) pin 6 ORG(+) --------------()------------BLK(-) pin 8 Button 7800 control (buttons) /----------YLW(-) pin 9 Button L / /---------()---| YLW splits / \----///-----\ pin 6 ORG(+) -------| ORG splits 620 ohm |---BLK(-) pin 8 \ /----///-----/ \---------()---| 620 ohm Button R \RED splits \----------RED(-) pin 5 7800 control (buttons) with SEGA wires /----------White(-) pin 9 Button L / /---------()---| Black splits / \----///-----\ pin 6 BLUE(+) -------| BLUE splits 620 ohm |---Black(-) pin 8 \ /----///-----/ \---------()---| 620 ohm Button R \Brown splits \----------Green(-) pin 5 Edited June 23, 2008 by Almost Rice Quote Link to comment Share on other sites More sharing options...
cosmosiss Posted June 23, 2008 Author Share Posted June 23, 2008 Too bad you did not get dual joysticks. Robotron rocks when played with the proper controller. You have the opposite problem I have, 1 joystick but 6 buttons in total. I have 2 sticks and only 2 buttons. I need to find our where I can get a couple of buttons. A two-stick panel would be awesome! Not only for Robotron, but for two players too. I have the coupler for the 5200, but I mostly play it in MAME, with the two player X-Arcade. Doesn't get any better than that, unless you own the machine Quote Link to comment Share on other sites More sharing options...
cosmosiss Posted June 23, 2008 Author Share Posted June 23, 2008 2600/7800 pinouts: _________________ \ o5 o4 o3 o2 o1/ \ o9 o8 o7 o6 / \___________/ Female pin # 2600 control 7800 control Sega Genesis extension cable 1 WHT- Up WHT- Up Brown 2 BLU- Down BLU- Down Red 3 GRN- Left GRN- Left Orange 4 BRN- Right BRN- Right Yellow 5 unused RED- Button (R)ight (-) Green 6 ORG- Button ORG- Both buttons (+) Blue 7 unused (+5v) unused (+5v) Grey 8 BLK- Ground(-) BLK- Ground(-) Black 9 unused YLW- Button (L)eft (-) White I'm going to find this section particulary helpful. No need to kiil any more controllers now. Quote Link to comment Share on other sites More sharing options...
Almost Rice Posted June 23, 2008 Share Posted June 23, 2008 (edited) I noticed I kept having to check where each wires went. So I took the FAQ and modified it and saved it on my PC. I did it because Sega cords are still readily available. I have been picking up Sega controllers whenever I can for a buck or two. When I decide what I want to do, I will be ready. It is also nice that they are 2600 compatible without mods. Edited June 23, 2008 by Almost Rice Quote Link to comment Share on other sites More sharing options...
cosmosiss Posted June 23, 2008 Author Share Posted June 23, 2008 Wait, I thought that was for the Sega Genesis controller cords. I see it's for the extension cords? Do they all have the same cable colors? I see they sell generic ones and Sega brand ones too. Quote Link to comment Share on other sites More sharing options...
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