Joystick hacking problems

[craiso]

Greetings,

I have a joystick for my rig that I have hacked and works for the most part. The problem that I am having is that when I hook everything up, I get multiple button presses. My wiring is not shorted and the PCB is properly wired. I test the buttons individualy without being hooked up to my harnesses, they work as advertised. Do I need to put some of those rectifing diodes in line with my switches?

Many thanx, Christopher

[Bob Reed]

What did you do, change the lengths of the wires to them? If that is the case you may have changed the impudence of the switch causing the problem you are seeing.

[craiso]

2 of the buttons work fine. The others use 2 wires that are common. I am only using 1 of the common wires and the buttons that work off of that common wire. The PCB that I am hacking is MS sidewinder forcefeedback 2.

Christopher

[JBaymore]

Christopher,

Not to be too simplistic here but are you using momentary contact buttons for your replacement buttons?

best,

....................john

[magicaldr]

Are you using the same button types between the 2 that do work and the 2 that dont? Sounds (and electronics was looong time ago) like the switch is bouncing.

We used to build de-bounce circuits for microelectronics back then. However I would have assumed this was part of the joystick controller already.

[craiso]

I am using momentary switches. I have the buttons I need working. I was just looking for a solution to get everything working together. I have 2 other controllers that have similar reactions, but I have just used what I could get to work. I don't think it would be a wire/switch impedence problem or a button bouncing. I thought that someone may have run into this problem and found a solution. I appreciate all the thoughts.

Many thanx, Christopher

[Bob Reed]

Do you have the same number of wires from the controller to the buttons? Some of the joystick interface, especially the ones with hat switches, use a voltage difference to tell what switches are being depressed. So thats why I was wondering about the impedance..

[Trevor Hale]

2 of the buttons work fine. The others use 2 wires that are common. I am only using 1 of the common wires and the buttons that work off of that common wire. The PCB that I am hacking is MS sidewinder forcefeedback 2.

Christopher

YES You will need Diodes. Place the diodes on your wires with the black line towards the switch, and that should solve your issue. Use any diode you like. 1n4148 will work best, but that should solve your issue.

Trev

[craiso]

I'll try the diodes. I have a few left over from my LPTswitch box.

Christopher

[Kennair]

Also Christopher many joysticks don't like it if all pots aren't connected and the typical symptom is jittery axis and multiple button presses. Attach either a pot or a suitable dummy load resistor to any unused axis and it'll fix it. Yes I had the same problem.

However you may have already tried this, or are using all axis, in which case Trevor's diodes will help. From memory though diodes only help if you are pressing many switches at once.

Good luck.

Ken.

[Bob Reed]

Also Christopher many joysticks don't like it if all pots aren't connected and the typical symptom is jittery axis and multiple button presses. Attach either a pot or a suitable dummy load resistor to any unused axis and it'll fix it. Yes I had the same problem.

However you may have already tried this, or are using all axis, in which case Trevor's diodes will help. From memory though diodes only help if you are pressing many switches at once.

Good luck.

Ken.

In a matrix, if you press one switch you stand the chance of back feeding a second or more switches which turn them to on. The diodes keep that from occurring as current only flows one direction through the diode.

[Kennair]

OK thanks Bob. Does that mean you should always connect diodes to joystick buttons then?

Ken.

[Trevor Hale]

It depends on the way the manufacturer connects the switches to the interface. I have found for instance with CH Yoke, they use the matrix, and therefore they use diodes, Just count the number of wires going to the switches, and if there is less wires then switches then chances are pretty good there set up in a matrix, and therefore diodes are required. Keep in mind that a diode cannot harm anything. Better to be safe and put them in. :)

[Kennair]

Thanks Trevor, that explains why I have found anomalies in some joysticks I've used. I have used diodes in one and not in others, and some are OK without them while others aren't. You're right though, they are a very inexpensive addition so might as well put them in.

Ta,

Ken.

[craiso]

The diodes did the trick. On a cpuple of buttons I had to put them on both wires in opposite directions. Thanx for all the help. When I get a chance I will post some pics of my force feedback stick on steriods...

Christopher