Hello all

Just went back to re work my MPCNC you know give her a tune up show her some Love.
I am using a ramps board and I can’t seem to get my end stops working.
X and why do nothing (The led does light when triggered but the motors keep rolling).
and Z resets the ramps board? I’m running 402 bug fix 2.0
any help at all is appreciated.

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Just a quick reminder that the endstops are only enabled/useful/given any sort of power/dignity during the homing process. Otherwise, the default behavior is to use softstops (the firmware just keeps track of where it is, and where it “can” be). You’d have to twiddle the configs and recompile to get the firmware to respect the endstops during operation.

This also assumes you’re running the dual endstop firmware in the first place… :wink:

All very good info, And I thank you. but my end stops did work in the past, and i do not understand why and end stop would reset the system.

What exactly did you do when you reworked/tuned up?

Please share as much as you can about what changed. That endstops worked before and don’t now is not enough scent for the dogs to follow.

I agree with your confusion on a z stop resetting the board. It shouldn’t happen, but I can think of at least 2 ways to wire a switch that would give this result.

You know I thank you very much for your help with this. My CNC has sate idle for some time. What I am going to do is take it down and give it a good overhaul. I think that’s best and it should save you guys some time with all my dumb questions.

A few things to consider. First, the above issue is bad. It is highly likely this means that when the endstop is triggered, it is shorting power to ground somehow. Ramps boards do not deal well with this kind of problem, and frequently this kind of shorting will burn out pins or blow a voltage regulator on the Mega board.

A few other thoughts. You mention the LED coming on. I assume you are referring to the LEDs on the endstop boards. If so, be aware that I’ve never seen anyone get this type of endstop working with a normally-closed configuration of Marlin. These boards come wired normally open, and even switching the pins around does not result in a valid normally closed board. Typically, I see people remove the switch from the board to solve the problem, or simple buy some bare switches and get rid of the boards.

Did you upgrade your firmware at some point? If so, is it possible that your old version of Marlin was set up for normally open switches before the upgrade?

If your switches were not rebooting your machine, I would suggest you start by using M119 g-commands and trigging individual switches by hand to see what Marlin is sensing with each switch.

If you are using the switches on the little circuit boards, I suggest you toss them and rework your system to use the bare endstop switches. This eliminates the VCC wire, so as long as you plug the endstop switches in correctly, you cannot short VCC to ground.

Also, if somehow you ended up burning out a signal pin, it may be possible to reassign that endstop to an alternate pin on your board. To clarify, the normally-closed setting of the endstop switches is set in the firmware and can be easily changed. Normally closed is a bit safer since, if a wire is knocked loose, the homing stops rather than trying to drive the trucks through the end of the machine. That is why normally-closed switches are the default for the V1 maintained firmware.