Endstop wiring question

Mostly Printed CNC - MPCNC Troubleshooting
1

Hello All,

I’m in the process of building my Primo and came across a dumb question about the endstop wiring that I can’t seem to find the answer anywhere.

I know that I should use the ‘-’ and ‘S’ pins on the motherboard (RamBo v1.4) and the ‘NC’ and ‘C’ pins on the endstop, however it doesn’t mention anywhere if I should connect the ‘S’ to the ‘NC’ or ‘C’? Or does it not matter which one I connect to as long it completes the circuit?

Thanks in advance

2

It does not matter. The switch will keep them closed until the paddle is hit, the. It will open the circuit.

3

It doesn’t really matter.

By convention, when I set these up, I connect (S) to (C) and (-) to (NC). My reason is this: If I then connected (+) to (NO) this would also provide appropriate logic if the pullup resistor isn’t working, where the (S) pin is logic level low unless the switch is triggered, in which case the (S) pin should be logic level high. It gives me another option that will always ensure that I never short (+) straight to (-). (Full disclosure, I’ve never used it. I did have a broken pullup resistor on one board, and I just clamped in a pullup resistor at the board connector between (+) and (S))

4

so crazy, changing out the endstops worked, the other ones needed voltage and were always saying triggered, thank you for everyone who helped, much appreciated!

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