@dc42 Thank you very much. I have ordered the materials and will try. I cannot put the Duet3d filament monitor on it because it has to be narrower to fit. Thanks.

Hi everyone, my name is Ruben and I`m new to the forum.
I'm trying to make a filament runout to connect to the roto toolboard on the 3.3v pins (IO 2).
I don't know anything about electronics other than putting in an LED, in terms of electricity a relay would be enough, but for me this is more complicated.

The idea is that when the switch is in OFF (Open) the red LED is on and sends the signal to the roto toolboard, and when the switch is in ON (Closed) the green LED turns on and the red LED turns off.

I think that an analog switch is equivalent to a relay, I'm leaving the schematic here. If anyone can help me, I'd be grateful. Thanks.