My pause.g is:

; pause.g
; called when a print from SD card is paused
;
; generated by RepRapFirmware Configuration Tool v2.1.8 on Fri Mar 20 2020 05:06:07 GMT-0700 (Pacific Daylight Time)
M83            ; relative extruder moves
G1 E-10 F3600  ; retract 10mm of filament
G91            ; relative positioning
G1 Z5 F360     ; lift Z by 5mm
G90            ; absolute positioning
G1 X0 Y0 F6000 ; go to X=0 Y=0

I haven't tried it for a while but I believe it did the same thing when I had an issue with the extruder skipping. Additionally I think this line from running M122 says that the duet 3 hasn't reset:

Last reset 01:23:10 ago, cause: software
Last software reset at 2020-04-11 15:21, reason: User

So I've got my magnetic filament sensor working correctly (using a duet 3) with a microswitch. The problem is when I trip the microswitch (unplug it actually) the printer just stops (pause.g/pause button moves to x0 y0) and DWC says disconnected and reconnects. Once it reconnects it says that filament ran out and so paused, but the pause button isn't lit.

Anyone know what is going on with this or where I can start debugging it?

I just got one of the magnetic filament sensors and I have two questions about the switch provisions for having the magnetic sensor post extruder and switch before:

1. Should the filament switch be open or closed with filament present (and is it configurable)?
2. The switch I currently have has a LED with resistor and capacitor that seems to ground out to the chassis (though at mega ohms of resistance), is it going to cause issues to have this switch plugged into the magnetic sensor? I can probably remove the led et al and remove that path but I'd rather not if not needed.

@dc42 Thank you!

That is fantastic! Just to confirm, I should be fine to wire the power and ground of the sensor to the 24V (directly to PS or maybe OUT_2) and the signal wire into the one of the IO headers (say IO_6).

Please forgive my ignorance about diodes on this...

According to the wiki at https://duet3d.dozuki.com/Wiki/Connecting_a_Z_probe#Section_NPN_output_normally_open_inductive_or_capacitive_sensor it says to use a bat43, bat85 or 1N4148 diode but I've only been able to locate a UF4003 and 1N5821 from the shops that are open (quarantine FTW). Will either of these work/be safe for a duet 3 or should I wait until I get a 1N4148 in the mail?

Thank you, this was very helpful!

I've been digging through the forums trying to better understand how the three jumpers for 5V work on my new duet 3. Specifically, I'm wondering about the safety of having the internal supply jumper (INT 5V EN) jumped while using both the USB power and 24V. I found a post from 2018 that I think is about duet 2 which says this should be safe, but I want to double check for the duet 3.

Additionally, if USB is provided and the internal source is enabled, which provides the power and what will happen if one is cut off? (ie if the USB or 24V supply shuts off, will the SBC and duet internals keep getting power?).

And finally, if the duet 3 provides the power while both are connected, is there any concern with back feeding into the USB power?