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Can the 5V line in the 7800 Controller...

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On Osgelds Nes controllers he had a 2 small LED running on the board, I'm sure that was off that 5v line.

Good point, I actually have two of those controllers, my question/answer should have been obvious to me!

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Hey so I ordered these:

 

https://www.ebay.com/itm/Small-Night-Lamp-100-500-1000PCS-5mm-LED-Light-Bulb-Emitting-Diode-Muti-Colors/142644848371?ssPageName=STRK%3AMEBIDX%3AIT&var=441624165971&_trksid=p2057872.m2749.l2649

 

Driver Voltage: 1.8-3.4V (is that ok?)

 

Reading up it looks like I need to add a resistor on these things or they will burn themselves up. How do I figure the safe value to pick a resistor? (I have tons of the resistors I uses in 7800 controllers but am not sure they are a good match)

 

And every time I ask these basic questions I keep saying I will go find a beginners book and learn. I'd take suggestions on that too!

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Good point, I actually have two of those controllers, my question/answer should have been obvious to me!

 

 

yes the led and the micro controller run off the 5 volt line, its just connected to the system's regulator

 

 

https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-led-series-resistor

 

"driver voltage" i assume is the forward voltage of the LED, ie how much voltage is needed to go though the junction of the diode before it starts conducting

Edited by Osgeld
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https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-led-series-resistor

 

"driver voltage" i assume is the forward voltage of the LED, ie how much voltage is needed to go though the junction of the diode before it starts conducting

Thanks! a calculator like this is perfect.

 

If Driver voltage is the forward voltage then it's 1.8-3.4...should I use the higher or lower value? The way you word it (before it starts conducting) I assume the LOWER value.

 

Supply is 5v. I got that.

 

But how do I find the third value it wants for Forward Current If (mA) ?

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different color led's are going to have different forward voltages, one can assume that red amber and green are going to be around 2.1 volts, blue and white and purple are going to be around 3.2 so use those numbers as a basic guideline (you can use a multimeter if it has a diode function to tell you exactly what they are as each led will be slightly different, but lets be realistic)

 

the seller doesnt tell you how much power those things can handle or how much light they will put out at what current (like blue is generally stupid bright and amber not as much) but again you can assume the max current a generic though hole LED can handle would be up to 25 miliamps

 

That will give you a starting point of max then you can tweak from there

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Thanks SO much Osgeld!!!!

 

I went with red so I'll call it 2.1 for now (ordering from China, I may not see these for a month).

 

Using 5v for supply, 2.1 for forward voltage, and 25ma for Forward current puts the resistor value at 116 ohms, so I guess I am likely going to use a 150 ohm resistor.

 

 

And I am bringing this home from the store tonight:

https://www.hamiltonbook.com/electronics-workshop-companion-for-hobbyists

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hey maybe you guys can help me diagnose ANOTHER issue I am having. I built a series of controllers. I wired up the first one based on the diagram Wyuli Wolf put up here a while ago.

 

Well, I cannot do down left and down right input combinations (Diagonals). But down works fine, and Right/Left work fine. It is at best jittery, at worst, completely non-responsive doing diagnoals. Button presses may affect this to some degree but it could also be my imagination as it is so inconsistent in it's behavior--like sometimes I think it controls better with a button held down but other times it just seems bad peioid.

 

I am using generic arcade sticks from China and real 7800 cords. I do test cords before using them for donors, but as we all know 7800 controllers don't control great anyway. So if I can get 8 directions and the buttons to fire once on the stock controller, I assume the cord is good. With this controller on a joystick tester, I can get 8 directions to register...I just have to be in a TINY exact spot for down/left and down/right.

 

I'd actually blame my wiring etc first but the cheap zippyy stick in certain controllers I built months back are now acting weird. Most work fine, but ONE now has a VERY similar issue. So it almost seems like the stick degraded? The switches went bad? I'm lost!

 

I have checked my wiring 17 freakin times on the new one, and check all connections, and everything appears good to me. It could be, these sticks just suck, and a varying level of quality control with a bad stick could explain why some of my builds work and others don't (all wired nearly identically, if not identically). But does jittery controls like these suggest a wiring issue to any of you? A short? Anything? Something I messed up? I've tried to think of everything, I thought maybe resistors are directional, and I wired some wrong...apparently they are NOT directional. And the 7800 wiring is fairly simple.

 

Basically next I'm gonna step up my stick game, get a Sanwa and put it in, and see what happens. But I feel like this is something I should be able to solve!

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Did this stick ever work properly, say immediately after you wired it? Have you checked to make sure that the stick is not internally impacting the wiring? Is the stick's shaft straight? If you disassembled the stick at any point, are you sure that you reassembled the parts correctly?

 

If these are sticks that use standard switches that can be swapped out, try swapping the switches with each other and see if the symptoms change, for example, swap the 'up' switch for the 'right' switch(physically relocate the switches themselves,) If the switches are soldered on a board, rotate the board 90 degrees and rewire accordingly, and again see if the behavior follows the switches.

Likewise, to test the wiring, swap the 'up' wire(s) for the left or right. You might need to take notes in this case so you know what behavior is expected. See if the iffy control follows particular wires.

 

A picture or two of the bottom the stick, including the switches and wiring would be helpful.

Edited by fluxit
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fluxit one was my main stick, always worked well AFAIK...but on my 7800 I play very few 8 direction games. So I can't say that maybe I didnt miss it originally. Now it is jittery a shell. Stick is straight. I never disassembled it.

 

One I did at the same time is still 100% perfect.

These switches can relatively easily be switched in the joystick frame...I didn't think to as the left right up down work perfectly on their own. It is just a combination of down/left and/or down/right when i run into issues. Wouldn't that indicate the switches themselveswere ok?

 

Anyway, I will do a switcheroo of the switches to other positons ASAP, and see what happens... and take some pics. Thanks!

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The reason that I asked if the problem occurred immediately is twofold: If you haven't greased the actuator(the part on the shaft that actually switches the switches) where it impacts the restrictor gate(if any) or where it impacts the switches or their levers if there is no restrictor on that particular stick, normal wear after a relatively short period of time will generate fine plastic dust which works very well for fouling switches. This dust may or may not obey gravity. And switches don't necessarily foul completely. A fouled switch may still seem to work well when switched 'down' for example, but the change in angle(and usually depth as well) on diagonals can exhibit this problem. In addition, wire routing that allows your wires to be impacted can show this symptom over time as the wires are stressed and/or the connections are moved.

 

On the other hand, if you'd seen this problem immediately, my guess would be either you didn't center the shaft hole correctly in your case when you installed the stick, or again- wire routing issues. Of course it's always possible that you have one or more switches that were iffy when you got them and should be replaced. Cheap sticks tend to come with cheap switches.

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The reason that I asked if the problem occurred immediately is twofold: If you haven't greased the actuator(the part on the shaft that actually switches the switches) where it impacts the restrictor gate(if any) or where it impacts the switches or their levers if there is no restrictor on that particular stick, normal wear after a relatively short period of time will generate fine plastic dust which works very well for fouling switches. This dust may or may not obey gravity. And switches don't necessarily foul completely. A fouled switch may still seem to work well when switched 'down' for example, but the change in angle(and usually depth as well) on diagonals can exhibit this problem. In addition, wire routing that allows your wires to be impacted can show this symptom over time as the wires are stressed and/or the connections are moved.

 

On the other hand, if you'd seen this problem immediately, my guess would be either you didn't center the shaft hole correctly in your case when you installed the stick, or again- wire routing issues. Of course it's always possible that you have one or more switches that were iffy when you got them and should be replaced. Cheap sticks tend to come with cheap switches.

Man I'm going nuts. I wired up controller #2...similar issue. I went back and tightened every freakin connection on controller #1...still happening. I'm using one batch of donor controllers from eBay fro the cords and maybe I got a bad batch. At this point I just don't know. I also bought the sticks in a batch together, I think (it was a while ago)

 

(this theory doesn't explain why my older controller is acting off though)

 

Here is a pic of #1. Buttons fire fine and work as buttons 1/2 should, independently. Resistors are wired in on the bottom of the photo, they split by where the orange common fire splits.

 

CgoaSL1.jpg

 

I don't think it could be dust etc on the new controllers as the sticks were brand new. I actually really hope there is something stupidly wrong I am missing because this is pissing me off!

:lol:

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I have a joystick like that in my mini mamecade, I just took the green restrictor plate off it annoyed me in diagonals

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That's what I was going to recommend. Removing the restrictor plate temporarily at least should tell you if it is an alignment issue.

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ok im going to do that now. Will see.

 

EDIT: it feels better but it's still just getting hung up on quick movements. Straight up jittery and stopping. Now up left or down left. The fact that it keeps changing makes me think I used bad cords. I dunno.

 

I even plugged in the official 7800 joypad to see if something was weird with Xevious or my system, and it played great, immediately smoother.

 

Well, enough frustration for one evening!

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Do you actually feel it getting hung up? Some of those switch levers can have sharp edges that will bite into the actuator. They shouldn't do that.

Have the directions that don't work reliably actually changed on their own(without switch swapping?)

 

How's the spring tension? Is it enough to keep the stick fairly well centered when at rest?

 

Do the switches' levers all make contact with the actuator when the stick is at rest? If so, do some levers seem to have more immediate tension behind them than others? On this stick, when and where those levers make contact with the actuator determines how responsive a particular direction will be.

 

Depending on the tolerance of the switches, some may actually require more travel to activate then they should, but this should be a fairly consistent problem.

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It doesn't feel like it is getting stuck on anything. I can move the stick freely but it just seems to have the TINIEST and most inconsistent of spots for those diagonals.

 

The behavior does seem to change on it's own, at first it was down left and down right, now it's up left and down left. This seemed to be the case even after I switched Left and Up back and forth. Singly, left right up down, the switches seem completely fine.

 

Stick centers quickly and strongly.

 

The levers all seem to be about the same distance from the actuator. The levers all have very LITTLE tension behind them...when removing the switches I could shake the switch and the lever would wobble back and forth....but it does seem to return to a proper position after a directional input, that is, it bounces back.

 

I appreciate all the help man, I'm looking forward to trying a new, brand name joystick. That should at least tell me if it's the stick or the wires.

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It doesn't feel like it is getting stuck on anything. I can move the stick freely but it just seems to have the TINIEST and most inconsistent of spots for those diagonals.

 

The behavior does seem to change on it's own, at first it was down left and down right, now it's up left and down left. This seemed to be the case even after I switched Left and Up back and forth. Singly, left right up down, the switches seem completely fine.

 

Stick centers quickly and strongly.

 

The levers all seem to be about the same distance from the actuator. The levers all have very LITTLE tension behind them...when removing the switches I could shake the switch and the lever would wobble back and forth....but it does seem to return to a proper position after a directional input, that is, it bounces back.

 

I appreciate all the help man, I'm looking forward to trying a new, brand name joystick. That should at least tell me if it's the stick or the wires.

When you say you are using actual 7800 cords, are these cords you are actually cutting off the original 7800 (or Genesis) controllers or where did you get them from? I'm wondering if there is a connection, but a poor connection of the cord end to the controller receptable if these are 3rd party cords. I got weird arcade stick behavior because the extension cord connected to the 9-pin Dsub connector on the back of the arcade stick was not making firm contact with the extension cord that went from the arcade box to the console.

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When you say you are using actual 7800 cords, are these cords you are actually cutting off the original 7800 (or Genesis) controllers or where did you get them from? I'm wondering if there is a connection, but a poor connection of the cord end to the controller receptable if these are 3rd party cords. I got weird arcade stick behavior because the extension cord connected to the 9-pin Dsub connector on the back of the arcade stick was not making firm contact with the extension cord that went from the arcade box to the console.

Original 7800 cords from real controllers. I bought a donor lot off of ebay and tested them quickly. Even if they were a little off, if I could get two button play and all 8 directions, I figured cord was ok and blamed ANY issues on bad dome switches.

 

I just wired up the third controller and it has the same issue. This one can't do down and right. WTH am I doing wrong!!!! Argh!

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And you have tested with standard 7800 controllers and all directions and diagonals are good then? Because it is sounding more and more like a possible issue with the TIA itself. They are notorious for making everything look and seem like it is working, and then you try an AtariVox or plug in a gamepad controller or paddles, and find out that something suddenly doesn't work. Replaced at least two TIAs now in 7800s. Heavy Sixer TIAs have issues of their own and newer TIAs have collision bugs with certain 2600 games like Kool Aid Main...so I stick with TIAs that I've salvaged from 4 port units.

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And you have tested with standard 7800 controllers and all directions and diagonals are good then? Because it is sounding more and more like a possible issue with the TIA itself. They are notorious for making everything look and seem like it is working, and then you try an AtariVox or plug in a gamepad controller or paddles, and find out that something suddenly doesn't work. Replaced at least two TIAs now in 7800s. Heavy Sixer TIAs have issues of their own and newer TIAs have collision bugs with certain 2600 games like Kool Aid Main...so I stick with TIAs that I've salvaged from 4 port units.

 

I've tested with a nice 7800 gamepad and it is totally fine (awesome, actually. I underrated these pads. Same game to test, Xevious). I've tested an eBay bought Pro Line and it's janky, but I assume that may be why I got them basically 4 for $24 (the first three I used for the donor cords for these sticks.....).

 

Still, now one of my old builds is also like this. I built it over a year ago, and I believe donor was totally fine. But one of my old builds is still ok. I am so lost. Seems like I MUST be doing something wrong. :mad:

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you are

 

HAHAHAHAHAHAHAHAAHA

 

wait, that's not helpful

 

since you wired everything with spade lugs have you tried disconnecting the direction wires and just touched them to ground, if you unhook R and down and touch them to ground does it go diagonal (2600 combat is a great test cart for this)

 

if that is no problem then you have eliminated one variable

 

glory of electronics, its the simplest crap that always causes you grief, so start simple and work from there ... a multi-meter would help, if you have a harbor freight near buy keep a look on their site, they often give one away that is perfectly acceptable for home and hobby use for free with a purchase ... and its horrible fright, you can ALWAYS find some tool you want or need for just about nothing

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Original 7800 cords from real controllers. I bought a donor lot off of ebay and tested them quickly. Even if they were a little off, if I could get two button play and all 8 directions, I figured cord was ok and blamed ANY issues on bad dome switches.

 

I just wired up the third controller and it has the same issue. This one can't do down and right. WTH am I doing wrong!!!! Argh!

How many games have you tried it with?

 

The fire buttons have pin6 as a common while the joystick has pin 8?

Pin 8 connects directly to resistors that individually attach to the leads to pin 5 and pin9?

the resistors are about 600ohm, not 600 kohm?

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How many games have you tried it with?

 

The fire buttons have pin6 as a common while the joystick has pin 8?

Pin 8 connects directly to resistors that individually attach to the leads to pin 5 and pin9?

the resistors are about 600ohm, not 600 kohm?

backwards

 

joystick is switched direct to ground, just like a 2600

 

the buttons are pulled down to ground via resistors so they can either register as a digital low for 2600 mode or an analog low on 5 and 9 paddle pins for 2 button support on the 78

Edited by Osgeld

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