ESP32 Stepper Driver Library Issue

Question

I have been having a wired Issue which I couldn't solve during the last two days :( I'm building a winding machine using a stepper. The Stepper runs fine with basic Arduino code but the stepper only vibrates strangely when using a Stepper Library such as Acellstepper or the Arduino Stepper Library. I've tried Full and Microsteps but same result.

Hardware overview:

I'm using a Bigtreetech TMC2208 driver with a 1 amp Stepper Online Nema 17 and a standard ESP32 as a brainbox. The TMC driver is configured for legacy mode (UART is also possible) and I had to swap two motor leads because for some reason the Driver has a different Coil Pinout than a standard A4988.

Wiring goes as follows:

GND - ESP GND

VIO - ESP 3v

STEP- ESP 25

DIR -ESP 26

EN - ESp GND

VM - 9v Powersupply

GND - 9v Powersupply GND

OB1,2 and OA1,2 to the stepper

This code works without issue, but I want to use a Library for acceleration and easier distance calculations.

// Motor pins
#define Step 25
#define Dir 26

#define ENCODER_PIN_A 12
#define ENCODER_PIN_B 13

volatile long pulseCount = 0;

void setup()
{  Serial.begin(9600);
  pinMode(Dir, OUTPUT);
  pinMode(Step, OUTPUT);
  digitalWrite(Dir, LOW);

  pinMode(ENCODER_PIN_A, INPUT_PULLUP);
  pinMode(ENCODER_PIN_B, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(ENCODER_PIN_A), handleEncoderInterrupt, CHANGE);
}

void doMotorStep()
{
  digitalWrite(Step, HIGH);
  delayMicroseconds(350); //lower = faster, but louder
  digitalWrite(Step, LOW);
  delayMicroseconds(350);
}

void handleEncoderInterrupt() {
  int encoderA = digitalRead(ENCODER_PIN_A);
  int encoderB = digitalRead(ENCODER_PIN_B);

  if (encoderA == HIGH && encoderB == LOW) {
    pulseCount++;
  } else if (encoderA == LOW && encoderB == HIGH) {
    pulseCount--;
  }
}

void loop()
{    
  doMotorStep();
}

On the other hand, this simple Accel-Stepper example only causes vibration from the stepper.

#include <AccelStepper.h>
#define stp 25
#define dir 26

// Define a stepper and the pins it will use
AccelStepper stepper(1, stp, dir);

void setup()
{  
  
  //Stepper Setup
  
  stepper.setMaxSpeed(40);
  stepper.setSpeed(20);
  //stepper.move(5000);
  

}


void loop() {
  stepper.runSpeed();


}

If someone has any suggestions where the Problem might be I would be really grateful. I've bee troubleshooting this for 2 days but got nowhere so far.

Answer 1

I think that first you must use stepper.setMinPulseWidth(##minimum pulse width ##) since it is initially 1 microsecond. Another thing is that the speed you set is not suitable to what you are expecting from your basic code.

What you are getting from Accel-stepper is equivalent to this in your basic code:

  digitalWrite(Step, HIGH);
  delayMicroseconds(1); //lower = faster, but louder
  digitalWrite(Step, LOW);
  delayMicroseconds(50000);

You can try it in your basic code to see if you are getting the same strange vibration and then try to set the good parameters in Accel-stepper.