@phaedrux I am making a small board that will fit on the hotend and take care of reading the pt100 and turning on the heat sink fan when needed (removing the need for the duet to care about that fan or run wires to it) as well as normalizing the pwm signal for the part cooling fan and bumping up the pwm frequency fed to the fan to something it can deal with and utilizing the tach input from the fan for feedback.

I'd still need to feed the temperature back to the duet and the easiest way would be to send a pwm signal up the thermistor line.

The other pwm input pins were for a different project where I wanted to send force feedback to the duet for a dimensional probing toolhead with a load cell. but we can ignore that for now, I was just hoping a solution for that would fall out of the pwm temp feedback.

Is there a straightforward way to read a pwm signal as an input on the duet 2 wifi + duex with rrf? I know I can probably filter it down to analog and utilize the a2d converter but that sounds rather roundabout when I have a solid pwm input signal to begin with, and I'm not sure if there will be artifacts from the ripple from the pwm lining up with sampling frequency creating a beat frequency. I'd rather avoid that whole possibility.

I will need about 8 inputs but less would still be useful for development, and it would be slightly preferable to use the thermistor inputs but that is not a requirement. I don't want to do serial as I really only need to send one continuous variable and pwm should be solid over less than ideal wiring.

One signal i would like to feed it into is the temperature pid loop replacing the thermistor. the other is for a sensor and as long as I can query its current value via gcode I'm good.

I would say I found the issue if this were not my working PT100. doh. I tested with a 100ohm resistor and the daughterboard seems okay, the only thing left is inside the pt100 itself which seems randomly unreliable. I may just switch them both back to thermistors, It would be nice if micro fit 3 pigtails were available at the e3d store to repair this sort of thing.

It's a genuine e3d one.

Hmm.. it's possible 16 ohms snuck in somewhere, I'll disassemble things and see if i can find it. The wire connections directly to the pt100 feel really fragile, I wonder if I damaged them up when doing a nozzle change.

removing the back panel of the toolchanger is kind of a pain when all the captured nuts fall off, it's about time I design a magnetic mount for it.

I have an e3d toolchanger with the duet 2 wifi and two of my toolheads have PT100 sensors connected to the same daughterboard. They were working great for several months and all of a sudden, one of them reads 40C higher than the other. It appears to be tracking temperature correctly comparing the two, just 40C off. Any ideas? The connectors all seem to be snug.