Basic Information: Printer Model: Peopoly Magneto X MCU / Printerboard: Magneto X Toolhead v1.1 klippy.log N/A Rationale Button debounce is a common problem, and “add a pull up resistor” is not always practical or the appropriate fix. For example, some mechanical switches have bouncy by their ve…

Ok, I posted a PR: Debounce gcode_button and filament_switch_sensor master ← garethky:pr-debounce-filament-switch opened 05:53PM - 11 Mar 25 UTC (UTC) [imag…

This references buttons, IDK if OP meant homing? Do they mean gcode buttons? @EmperorArthur can you explain what buttons you are talking about? The homing debounce check for switch pins is in the endstop c code so that single “triggers” of a switch are ignored. When the switch triggers the first ti…

You’re correct that I do not mean homing. I have no idea where that came from. I was not aware that endstops already perform debounce checks. It’s relevant to this discussion in it shows other places where that type of code is used. I was specifically talking about klippy/extras/buttons.py . Whic…

[image] EmperorArthur: Looking through the code, filament_switch_sensor registers a button with a callback under the hood. That button code just seems like the logical place for debounce code to live, but I’m not that familiar with Klipper internals. If I’m not mistaken, the buttons already d…

Yes, there is some debounce magic in buttons.c . But I think this only requires that the button is pressed for 2 reads. And reads happen pretty frequently, every 2 milliseonds That’s a very short amount of time on a human scale (the blink of an eye is ~150ms). So its possible that manipulating the f…

[image] garethky: The option event_delay defaults to 3 seconds and it ignores duplicate events during that time. So the macro cant be triggered more than once every 3 seconds. I think I see the confusion. You’re thinking about debounce for multiple events. Which can be an issue. However, I…

@EmperorArthur Sorry about being flippant earlier about the filament sensors - as you’re discovering, most of them out there are, well, crap. In my experience, I have found that a filament sensor must have a filament motion sensor to be truly useful. Just having a mechanical sensor (such as the b…

No worries. I will be adding more sensors when I build the 3MS MMU. However, the false trigger issue seems to be the nature of the switch based sensor. It’s common enough that I think the development effort is worth it. Especially since doing so in the “button” code would deal with multiple scen…

Well a good step 1 would be to hack together something that solves your problem. Then we would at least know if debouncing is a solution, and if so, just how much is required for it to be effective. I could see a macro that only alerts that filament has run out if the switch stabilises in the trigg…

I just saw the response from @garethky and rather than look at the software, my suggestion would be to use a filament sensor that isn’t mounted on the toolhead. Peopoly probably placed the filament sensor there because if there is a break in the filament or if it runs out, you get an indication wi…

As I have a MagentoX as well: My interpretation is that the filament sensor is causing spurious triggers even if filament is present. Thus, this would be attributed to the mechanical design of the sensor rather than its electrical characteristics like bouncing.

Proposal: Button Debounce

Features

Topic		Replies	Views
Debouncing endstops General Discussion	15	334	February 28, 2025
"filament_switch_sensor" debounced with timeout General Discussion	3	208	October 5, 2024
Debounce_delay in filament_sensor General Discussion	5	157	October 21, 2025
Gcode_button and logic General Discussion	9	1521	January 24, 2024
Event_delay in filament_switch_sensor not doing what I think? General Discussion	1	1117	April 13, 2023

Proposal: Button Debounce

Related topics