I have some questions about the stepper driver modules.

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discussion
(Nathaniel Stenzel) #1

I have some questions about the stepper driver modules. Does a high signal on the direction mean it goes one direction while the low signal means it goes the other direction? Does the step pin need to go high and then low again to take a step or does it step when it goes high or does it keep stepping as long as it is high?

(Justin Nesselrotte) #2

There is usually a direction, step, and enable. (The specifics could be wrong regarding high/low here)

A high for the direction pin is one way, low is the other. Enable being high enables the stepper motor.

The step pin must toggle to do a single step. It will not continue to step in any state.

(Nathaniel Stenzel) #3

@Justin_Nesselrotte thanks much. :slight_smile:

(Ryan Carlyle) #4

High/low logic depends on the driver. Some are low to enable or low to step. Steps typically register shortly after the step pulse leading edge, ie for high logic it is the rising edge plus a short hold (ie 1us) that triggers the step.

A fun problem is when the controller outputs inverted high/low logic on the step line… you’ll end up with one less microstep in each run of steps in the same direction. Creates some wacky drifting that depends on object geometry.

(Nathaniel Stenzel) #5

@Ryan_Carlyle thanks much for the information on the oddity to watch out for. I will try to keep that in mind if I make my own motion control system.