I was following this tutorial:
https://www.makerguides.com/drv8825-stepper-motor-driver-arduino-tutorial/
I altered the source code to make it step very slowly (note that I am using "delay()" not "delayMilliseconds()")
#define dirPin 2
#define stepPin 3
#define stepsPerRevolution 200
void setup() {
pinMode(stepPin, OUTPUT);
pinMode(dirPin, OUTPUT);
}
void loop() {
digitalWrite(dirPin, HIGH);
for (int i = 0; i < stepsPerRevolution; i++) {
digitalWrite(stepPin, HIGH);
delay(20);
digitalWrite(stepPin, LOW);
delay(20);
}
delay(1000);
digitalWrite(dirPin, LOW);
for (int i = 0; i < stepsPerRevolution; i++) {
digitalWrite(stepPin, HIGH);
delay(20);
digitalWrite(stepPin, LOW);
delay(20);
}
delay(1000);
}
I have this motor:
https://datasheetspdf.com/datasheet/17HS4401S.htmlI am using a 12v 2amp switching "wall wart" power supply

the drv8825 looks identical to the Pololu, but does not have their logo.
I followed the advice in the tutorial and cautiously set the potentiometer so that my voltage meter read a vref of .5 volts, and tried an abcd and a bacd wiring; neither rotated.
I tried fiddling with the potentiometer, that did not make it rotate.
I read many people having similar issues , the main advice that I saw was to switch around which of the 4 stepper wires go to which of the 4 pins on the driver. Therefore, I tried all 7 possible combinations:
abcd
bacd
cbad
dbca
acbd
adcb
abdc
none resulted in a rotating motor. I tried swapping my drv8825 for another one (I bought a pack of 5) and got the same result. I tried switching my stepper motor for another from the box, and again, same result.
so, I have adjusted-
* the connections to the motor
* the settings on the potentiometer
* the number of steps per second (now very very slow)
* swapping parts
I have not tried other power supplies. perhaps this is the issue? is 12v 1a wrong? is a switching supply a bad idea?
is there perhaps something else wrong, that I have not tried?
is it possible the circuit in the tutorial needs modification?
anybody have any advice on what I might try?