So, is this supposed to do something? Connecting it to a WS55-180 BLDC driver to a spindle without a hall sensor. I can't get the spindle to, um, spin using this. I have to go back to the potentiometer control. I might buy another spindle and try with that.
To determine if its the Gradus or the Spindle, measure the output voltage on the 0-10v terminal while sending M3 Sxxx commands, where xxx = 0-255 for Grbl 0.8, 0.9 and 0-1000 for Grbl 1.1