Hi there, I came across this article when looking for a solution to trigger FWD from the Duet2. When I bought the VFD I could not find the Huanyang and ordered a combo VFD/Spindle, the VFD not the best quality and terminal are different. It has Vin and GND for analogue as expected but no DCM marked. I am a newb but following your posts (which I am grateful for) to setup I eventually got to the same stage of controlling speed from the duet controller. I shorted the FWD to the same GND as the analogue and it all worked in test. Switch off and come back to do a cut then it seems nothing on earth will bet the FWD to trigger. I managed to trigger it with a high resistor shorting the analogue Vin to FWD but of course that is just creating a voltage divider which throws the spindle speed off.
I set about finding a solution to trigger the FWD and ended up here, the question is have you found a way to trigger FWD? I thought it might be possible from the Duet2 using the Fan PWM headers but as a newb I need advice.
Many thanks for considering.