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The X/Y/Z motor driver board,refer to this pic And how to up/down the verf of the motor driver board?
Refer to this pic The blue type of the A4988
Recommend verf of it is:
0.6V~0.9V
You should increase it by tightening the potentiometer(screw) if the verf less than the recommend verf.
The Red type of the A4988 Recommend verf of it is:
0.8V~1.1V
You should increase it by tightening the potentiometer(screw) if the verf less than the recommend verf.