This is a step motor control extension board that sits on top of Raspberry Pi (EXCLUDING Raspberry Pi Zero series) with camera control and limit switch inputs. The following are its features:
	
Single power supply for both Raspberry Pi and step motor, eliminates messy cabling
	
Can supply up to 1.8A of current per phase for a two phase bi-polar step motor
	
Programmable power level 
	
Two optically isolated ports for camera or creatively other devices (2.5mm stereo jack)
	
Two limit switch inputs that can be used for homing, limiting (3.5mm stereo jack)
	
8 micro stepping modes, from full to 1/128th 
	
Free Python based control software for focus stacking, photogrammetry, camera motion control and more
 
Here is a video running focus stacking control software.  
Python Software