what is the pitch
assuming it is 2mm… and your stepper is 1.8 degrees per step. then….
at 16 microsteps it is 1600 steps per mm [ ((360/1.8) * 16) / 2mm = 1600 ]
at 32 microsteps it is 3200 steps per mm
you can use the calculator here also if its something diffrent
hope that helps