Awesome - thanks for confirming!

I managed to get up and running pretty quickly in the end. tapping the probe seemed to take some effort to activate the LED and I wondered if it was just going to bash holes in my printbite during probing, but it works and amazingly well.

nice to know there is that possibility for MOD , I'll implement it when I come to another good reason to take the bed up , the default is fine for now.

And the probe is a totally brilliant solution, I cant get over being done with effector tilt and changing z offsets, measuring all the points again.

Im running an older Duet here, ethernet only 0.8.5 ;

Firmware Name: RepRapFirmware for Duet
Firmware Electronics: Duet 0.85
Firmware Version: 1.22 (2018-07-26b2)
Web Interface Version: 1.21.2-dc42

This machine started life as TP3D's beta KosselXXL few years ago. Still going strong. Tho recently Ive come around to changing over to linear rails, hadyn's magballs and the delta smart effector. Its pretty much wired up already now so will move on to commissioning and testing soon. But as is, crossing over from TP3D's old wiring breakout board , currently there is no MOD signal for altering sensitivity of the z probe.
Im not sure if that is a feature reserved to the newer Duet 2 firmwares , or its possible to run this feature also with my older HW.

I couldnt locate the right info easily on wiki etc, so Im hoping someone here might be able to help shortcut me to the answer!

If not, i'll keep with the 3 wire config, i've read on here already that the default is about right anyway.