How to trigger a pin on a board

Hey everybody,

I have the problem that I do not seem to know a basic thing: How do I trigger a pin on a board. I did google it but am not sure whether I found the right solution.

I want to trigger pin 7, autosquaring:

Can I just buy one of those ( and wire it to pin 7 (autosquaring) and pin 6 (ground)?

Any help is appreciated. :slight_smile:

What firmware are you running? Since it is a ESP32, I thought it might be FluidNC, but I did not find anything matching your diagram in my searches.

What control board are you using?

Assuming this is an input pin, it is highly likely that wiring a push button switch between pin 7 and ground is the correct wiring. It is pretty typical with microprocessors to use an internal pullup resistor, and for the pin to be triggered when it is pulled to ground. Assuming this pin is setup for input, testing to see if your auto squiring is triggered by grounding pin 7 is safe to do. When wiring switches to these kinds of pins, I use Dupont wires/connectors.

Note that the ESP32 board supports both internal pullup and internal pulldown resistors, so therefore it is remotely possible the pin will need to be pulled high (5V) to trigger. Whether it is pulled to high or low to trigger depends on what the firmware is coded to expect.

Thanks Robert, that helps. It’s this board that uses an ESP to enable dual endstops on estlcam.

Can I test it by just connecting two cables and holding them together? That’s what a switch does, right? :sweat_smile:

Would those work:

I’m going to assume the pins are looking for a trigger, so you want to briefly touch the wires together, not “hold” them together.

Would those work:

These should work. The amount of current is tiny, so any push button where the button is on when the button is pushed will work.

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You need to touch them at least 1.5 seconds per the configuration to not accidentally start autosquaring in the middle of a programme. But the general idea is right. :smiley:

Thanks so much for your help!

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