Button wiring.

[Herk]

Hey,

     Here is the scenario:  If button 1=a and button 2=b, how do I wire button 3=ab.  I am using micro switches and only these three buttons can be used in this scenario.

Thanks,

Herk

[Kevin Mullins]

So button 3= a+b ?

One side of your microswitch goes to ground/common as usual.

The other side goes to the action side of both button 1 and button 2.

Is that what you were asking?

[Chris G]

Perhaps if you explained the scenario there could be an alternate solution...?

[Herk]

Chris,

     I am modifying an x-arcade tankstick and have added a few buttons, one being an escape key.  The x-arcade circuit board has player2 + button4 = esc.  I want to have one button to be the escape key not the combo.


Kevin,

     I will try your solution right away but I think that makes all three buttons a+b.  Yup, all go a+b.  I need 1 to remain a only, 2 to remain b only and 3 to be a+b.

Thanks,

Herk

[BobA]

2 diodes inserted in the action side would prevent a and b buttons from interactiing.  Not knowing the ciircuit it would be trial and error in positioning them properly as to polarity.   If it does not work one way it is the other way.

[Herk]

BobA,

That sounds perfect, I thought restricting the flow would be more complicated than that.  Now for a lazy question.  What diodes do I need?  OK, I did a bit of quick reading.  I need regular p-n diodes.

Thanks alot,

Herk

[danny_galaga]

yep, you can pretty much use the cheapest, smallest diodes you can find at radio shack. its only a signal, so very small current.

[Tiger-Heli]

Another option -

From the picture, the tank stick looks like it is 26 inputs (16 buttons, two joysticks, 2 start).  There might be coin inputs that I am missing.

The X-Arcade DIY PCB is 28 inputs.

Assuming the Tank Stick uses the same PCB, you could just wire a button to one of the unused inputs and program it to send Esc.

Probably simpler than the diodes method.

[Herk]

Tiger-Heli,

     What is nice about the Tankstick is the flash memory program mode.  There are 4 modes. Mode 1 is for default MAME setup and is not programmable, 2, 3 and 4 are.  I want to use mode 1 with the extra esc button so I can't just program it to an open input.  Also there are two coin buttons on the Tankstick as well, one of which is the button 2=b in my scenario.  The diode way looks good to me.  I will let you all know when I wire it up, maybe later today.

Thanks for the help,

Herk

[superbigjay]

2 diodes inserted in the action side would prevent a and b buttons from interactiing.  Not knowing the ciircuit it would be trial and error in positioning them properly as to polarity.   If it does not work one way it is the other way.

Hello Herk, as BobA said, 2 diodes should do the trick.  Almost any diode that support 5V or more should do the trick.  If I remember my electronic, the orientation of the 2 diodes should be the cathode toward the NO port of your pushbutton 3.

Here a schem...

[Herk]

Superbigjay,

     That's great, it's always nice to see things visually like that.  I didn't get my diodes today.  Maybe tomorrow.

Thanks,

Herk

[superbigjay]

No prob,
I just had a refresh course on diode yesterday because I needed to hookup a P360 with a regular 4-way joystick on the same 4-inputs of the encoder.
Jay

[Herk]

Hey everybody,

     It works , it works .  Thanks to all that helped out.  I have exactly what I wanted using the diode method for a total cost of $1.99.

Thanks again,

Herk