My Stepper.h program is lagging when doing calculation

Hello!

I am having a problem with my code lagging when it is calculating the next step for a stepper motor.

My program runs by starting with a reading from a load cell using an HX711 amplifier. While reading a value greater than -0.25, the program runs smoothly. As soon as the value goes below -0.25 and uses the first and second else if starting in line 48, the program starts to lag.

If I comment out lines 48 to 55, the readings are very smooth and consistent. I think the problem is somewhere with the calculation of the next step in these lines.

I have also tried to force the scale.get_units to be an integer before calculation, but there was no difference. I also tried an stm32 nucleo f446re to see if a faster board would help, but it yielded the same result.

I have been troubleshooting, but have not found success. Any help would be greatly appreciated.

Thank you!

// Complete Code for Stepper Motor Control with Arduino and Force Sensor

#include "HX711.h"

HX711 scale;

#include "Stepper.h" 

#define Steps 200

Stepper stepper(Steps, 7, 6); // 6 Blue 7 Red

#define DAT 2
#define CLK 3

#define calibration_factor -19450.0 // determined through hx711 cal. code


int Step = 0;
int prev = 0;
int pos = 0;
int newstep = 0;

void setup() {
  Serial.begin(9600);

  stepper.setSpeed(750L);

  scale.begin(DAT, CLK);
  scale.set_scale(calibration_factor);
  scale.tare();

  Serial.println("Readings: ");
  
}

void loop() {
  Serial.print("Reading: ");
  Serial.print(scale.get_units(), 2); 
  Serial.print(" lbs");
  Serial.println();
  
  if (scale.get_units() > -0.25) 
  {
    Step = 0;
  }
  else if (scale.get_units() > -6.3) 
  {
    Step = scale.get_units()*334;
  }
  else if (scale.get_units()<= -6.3)
  {
    Step = -6.3 * 334;
  }
  Serial.print("Step");
  Serial.print(Step);
  Serial.println();
  newstep = Step - prev;
  stepper.step(newstep);
  pos = newstep + prev;
  prev = pos;
  Serial.print("ns");
  Serial.print(newstep);
  Serial.print("pos");
  Serial.print(pos);
}

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