Switches gnd to LED FET?

Now that I think about it, I’ll most likely just use the Positive line and go with the PullDown switch option, but I just wanted to ask how grounding a button to the hilt side pogo PCB works/doesn’t work. I mean, Blade Detect is just a latching switch and that goes through a FET.
I guess I get foggy on it because High Power LEDs current get regulated by the FETS with variable current levels, whereas with addressable pixels, the FETs are just on/off…?
So if the button uses the PCB negative, when the FETs “turn off” is there a loss of connection to GND then?
Sorry so poorly worded. Brain spewing confusion here. Need coffee.

So, the blade detect needs a fair amount of extra code to be able to be hooked up to a LED pad, and that code wouldn’t work if the LED pad was powering a regular led, which turns on/off 800 times per second.

When the FET is off, connection is lost. With neopixels, the pin still gets pulled high through the neopixels though, so it still works.

Thanks.
Oh, now that I look, PullDownButton is specified for 3.3v according to my notes…so full battery+ would be too much for a button pin?

Sorry…and then when you say

meaning the FET still works as a ground? Saying pulled high sounds like positive.

I’m just trying to save a path connection (button ground) through a removable chassis PCB by connecting to something on the back of the hilt PCB instead.

Most pins can tolerate 5v, so it shouldn’t be a problem to pull them high with battery power.

And no, the FET doesn’t work as ground when off. The pixel blade ends up pulling the pin HIGH, and the code still registers that as “blade connected”.

Perfect. Thanks for the clarification.
I guess the addition to the CONFIG_BUTTONS saying “PullDownButton” is just backward to my common sense at first, as we’re actually pulling the button pad high.
Pulling them low is the default.

The PullDownButton refers to the resistor inside the chip that pulls the signal down until you press the button.

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