I have the ‘Blink an LED’ program running on my Photon. D7 led blinks. I connected D7 to the STEP pin on the A4988. I noticed the voltage at that pin the collapses to around 1V and the LED does’t blink either. It should be around 3.3v. I unplugged power from the A4988 and it still happens.
WEIRD! I figured the STEP input on the A4988 was high impedance. Even with it unplugged from power, it still happens. Doesnt this seem weird? Anyone have good or bad experience with the A4988 Stepper Motor Driver Carrier from Pololu? I think I may have got a dud. Any input is appreciated!