New Design.

[CV Gus]

Earlier, I posted information on my digital 5200 joystick.

 

As you could see from the diagrams, it required tearing apart a regular joystick in order to install 2 "normally closed" switches for down and right.

 

But, Sunday, I finally managed a new design that uses ALL FOUR open switches! There is no need to open the joystick.

 

And so, the 9-pin digital joystick to 5200 adapter I'm building will not require the six relays and battery. So far, I finished the vertical. Today...the horizontal. So far, I'm using scrap parts, so progress is slow (some guesswork was involved, and trial and error- what do you want from parts from a 1970's VCR?).

 

The fire might be a bit tricky, but we'll see.

 

As for the 2600 paddles- yes, they work, but the fire buttons are actually left and right movement, so I'll have to install a switch for that.

 

The "keypad" is on the adapter itself.

 

This will be a nice little item.

 

[slampam]

Earlier, I posted information on my digital 5200 joystick...

 

This will be a nice little item.

 

Where? What? When? I missed this. Where's the link? Or repost it here.

[CV Gus]

Right here:

 

http://www.atariage.com/forums/index.php?showtopic=119395

 

Scroll down for the diagrams, which are here courtesy of Big O.

[CV Gus]

Oh, and yesterday I installed the horizontal circuits. So far, everything works as it's supposed to.

[CV Gus]

Well, it was inevitable, so it happened...

 

A PROBLEM!

 

 

The basics work just fine, but the neutral is not stable; it "drifts" and this can throw off the controls, maybe even causing unwanted motion.

 

Over the past two days I've narrowed it down to one likely place, and it's possible that the 10,000,000 OHM resistor I'm using is just too much, since even the slightest variation in current can cause serious problems at that high a resistance. My 5200 controller also might have such fluctuations, but the reistors aren't high enough to cause any problems, really.

 

So, when I can get them, I'll try (most likely again) 470,000 OHM resistors.

 

Incidently, CV controllers do not work. Probably the diodes they use; 7800 and most others I have do not.

[slampam]

You might wanna try my idea – take off the 5200 cover, reach down in there, get a good grip, and yank out everything with a quick, clean jerk. Then shove the innards of a XEGS in there and nobody will be the wiser. I won’t tell anybody…and a lot less frustrating.

[CV Gus]

No need- I solved the drift problem. Soon, it'll be built.

 

Then...7800 controller for a 5200!

[CV Gus]

There is no way this particular design can run a CV controller. It has to do with the diodes in the controller, and the fact that UP and LEFT in the module bypass the main potentiometer; this "switches" the polarity around. Even if you build it so the polarities are opposite, you won't succeed because then the other two directions will not work.

 

7800 controllers are the best by far for it so far. I do not know why, unless the switches in them are better than most others.

[CV Gus]

I attempted several modifications- with this design, you cannot use a CV controller.

 

The problem is, contrary to what a schematic might imply, that the "common" in a CV controller must be connected to positive. With an Atari 5200, the common is negative.

 

As a result, the only controllers that will work with this thing are those with EXTREMELY good contacts- and so far, the only one I have, really, is a 7800 Proline. Wicos might work, if they live up to their reputation. 2600 standard and TAC-3s do not, at least not very well.

 

 

 

(However, the first design- the one that uses a AA 1.2V NiMH rechargeable battery (others will also work) and six relays, two of them "normally closed," works with just about anything.)

 

The problem is clearly the resistance. So little current goes through, that anything less than superb contact points will cause problems.

Edited March 23, 2009 by CV Gus

[bohoki]

hmm a tac 3 should work great since i believe it uses a module that is identical to a grouping of 4 microswitches so you can just swap it out for 4 cherry microswitches and resistors using the typical plan

[CV Gus]

Well, the idea behind this thing is: you just plug in a regular 9-pin joystick, and the module into a 5200.

 

It works fine with a 7800 controller, and hopefully others. Again, the contacts in the joystick itself must be of very good quality. I guess even a 7800-5200 adapter is something, though.

 

 

The other design- the one that needs a battery, but is used the same (plug it into a 5200; plug regular joystick in to module), can be used with a CV, 2600, or most others. So- if I can get those relays I need, then I'll just build one of each. Once I do, then I'll try to post the plans for both.