Hi friends! i'm new in the world of astroberry and sorry for my bad english, but i need help about astroberry focuser. I've a raspberry pi3 and i try to use my nema17 stepper motor with A4988 driver using the bcm board on raspberry. I follow the tutorial on the main page of the astroberry focuser and it work, but it works very bad!! precisely when a i tried to move at some position in or out my stepper it does a random walk, doing some step in and some out in a random way! I've checked my pins connection but it is all correct respect to the guide on the website!
I am using the Astroberry focuser with Nema17 and A4988 driver with no problems, what voltage are you driving the stepper motor with. I use 12V and as mentioned on github have a 100mf capacitor protecting the power line.