Help Wiring EG Starts USB encoder to Sanwa microswitch

[R0CKY]

I have a working Arcade1up cab retropi conversion using the EG Starts buttons and USB encoder.

I am trying to swap out one of these buttons for a sanwa button, but I cannot for the life of me figure out the wiring and get the new button to operate.

In this photo you can see the current set up and I have the new white micro switch lying there for reference.

The existing buttons connect to the usb encoder with a 3 pin connection.

The Sanwa microswitch uses 3 spade connections though. So I split the existing cable and by touching 2 of the three wires together with retropie running, I figured out the two wires that operated the button. But when I connect these two wires to the new microswitch, nothing happens, the switch does not operate.

Where am I going wrong?

[leapinlew]

When you say you touch them to the new microswitch nothing happens, what prongs are you connecting to and are you activating the switch?

On the connectivity, it looks something like this, right?


And then you push the red button on the switch to activate the switch? If that's what you're doing, try a different switch.

[PL1]

I split the existing cable and by touching 2 of the three wires together with retropie running, I figured out the two wires that operated the button. But when I connect these two wires to the new microswitch, nothing happens, the switch does not operate.

Sounds like you have found the data and ground wires that Vocalitus identified here.

Those two wires connect to the microswitch COM (Common -- the bent one on the bottom) and NO (Normally Open) tabs.
- There should be markings or a diagram on the switch to identify which of the straight tabs is NO.
- Unless the switch is defective, pressing the microswitch will do the same as touching the wires together.  There's no polarity to the switch so it doesn't matter as long as the ground and data wires are connected to the COM and NO tabs.

                  ____ NC
COM ____/ ____ NO

Do not connect the third wire (5v) to the NC (Normally Closed) tab.


Scott

[R0CKY]

Hi Guys

What a relief to find an active forum at last - I've been struggling with this for months!

So, on the sanwa microswitch in my photo, there are two connections together (lets call them A & B), and the 3rd one is on the underside (C) . I was connecting to the 2 wires that I knew operated the switch to A & B. I tried them in both combinations, pressed the swicth, and nothing happened.

I had read somewhere that C was a ground, that's why I tried A & B.

Looking at your image posted above, maybe I should try B and C.

[R0CKY]

Sounds like you have found the data and ground wires that Vocalitus identified here.

Those two wires connect to the microswitch COM (Common -- the bent one on the bottom) and NO (Normally Open) tabs.
- There should be markings or a diagram on the switch to identify which of the straight tabs is NO.
- Unless the switch is defective, pressing the microswitch will do the same as touching the wires together.  There's no polarity to the switch so it doesn't matter as long as the ground and data wires are connected to the COM and NO tabs.

                  ____ NC
COM ____/ ____ NO

Do not connect the third wire (5v) to the NC (Normally Closed) tab.


Scott

Ah, I can see the bent one is labelled COM and the other two are both labeled NO.

I'll give this another shot - thanks.

[R0CKY]

It worked!!

I'll just solder those wires onto the COM (bent) and NO connection and good to go!

So pleased to have this button working at last, thanks for your help guys.

[PL1]

Ah, I can see the bent one is labelled COM and the other two are both labeled NO.

Either the switch is mis-labeled or one of those is an NC.
- A microswitch like yours won't have a spring-centered momentary push/pull like a "(on) off (on)" rocker switch.



When talking about switches, Common is not the same thing as ground.
- In some countries the terms "common" and "ground" are used interchangably.

If you connect your wires to NO and NC they will never connect because the COM lever disconnects from NC before it connects with NO a.k.a. "break before make".

Here you can see what's happening inside the microswitch.
- Before you press the actuator, the spring holds the COM lever (green wire tab) against the NC (blue wire tab) contact.
- When you press the actuator, the COM lever tab makes contact with NO. (no wire tab)




Scott

[R0CKY]

Makes sense, thank you for the info.