I recently got the smart filament sensor from Bigtreetech and have some trouble getting it to work with my Duet 2 maestro.
Since the 2 previous posts I found did not get it to work either and left me confused about the sensor type and pinout I decided to take mine apart to have a look inside.
After poking around with a multimeter I came to the following pinout:
| Out
-- GND
• Vin
I calculated the distance between the holes to figure out the pulse/mm and (if I did my math correctly) got 7.26mm which is close enough to the advertised 7mm detection length.
I added the sensor to the config.g using the following line and left R & E a bit high hoping to calibrate it later:
M591 D0 P7 C3 R0:200 L7.26 E25.0 S1;
Using the camera on my phone I could see the IR led so I assumed everything was wired correctly and started a print to have it collect data and calibrate but I got the following result during the print.
M591 D0
Pulse-type filament monitor on endstop input 3, enabled, sensitivity 7.26mm/pulse, allowed movement 0% to 200%, check every 25.0mm, no calibration data
At this point im stuck trying to figure out why this is happening.
I measured the voltage coming out of the sensor and it seems to be fluctuating between 2.44V & 2.58V. So it's not producing a pulse as I (and maybe the Duet) was expecting to see.
What would be the correct sensor type for this to work? I tried the Duet3D rotating magnet sensor with no success.
Alternatively would converting this sine wave to a square wave give the Duet the input it's expecting?