A4988 via ESP8266

Below is a very shotty diagram I made of my attempt at making a stepper motor be controlled with an ESP8266 (wesmos d1 mini 4v). But it doesnt work. Originally i had attempted the A4988 Stepper Motor Controller - Tasmota. but it also doesnt work, and i suspected it was because it was trying to use 3.3v logic when the stepper driver was being powered by 5v. during that attempt i killed a wesmos d1 because i gave it 24v down its 5v line by accident. Anyway i recreated what I thought was fine (from other example diagrams) using 3.3v power from the wesmos to power the stepper controller and use 3.3v logic, but it doesnt work either, im wondering if i broke the stepper driver as well, or maybe i just have an error somewhere, so i need a 2nd look at my diagram from someone who may be more experienced and see if they can see an issue.

I don’t see any obvious problems with your wiring diagram. Could you post some pictures of your actual setup that show all of your connections, as well as some close-up pictures of both sides of your A4988 carrier?

Also, could you clarify what you mean when you say “it doesn’t work”? For example, is it showing any signs of life and is the stepper motor energizing? Could you post more details about your setup such as what power supply and stepper motor you’re using, as well as what you set the VREF voltage to on the A4988 carrier?

Brandon

No power seems to be getting to the stepper, no vibrations or such.
VREF seems to only be getting me values between 0 and 120mV from min to max.

My calculations get me 200mV for 500mA max for steppers, the steppers are 35HS27MF405A

I think its safe to say I probably killed the stepper driver at the same time I killed the last ESP





Some of your solder joints look suspect, and there seems to be some kind of residue on your board (possibly excess flux from soldering?), but I’m not confident that either of those are bad enough to actually cause the issue. The VREF voltage only going up to 120mV seems odd too, so you might be right that it was damaged in your prior setup.

Brandon

Yep so the old driver board is fried, new one works like a charm, Thanks for the help

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