Interrupt to Stop an Stepper with proximity switch

Official Hardware Pro Solutions Portenta Machine Control
1

Hi all,

I have the following problem: I want to move a stepper motor with the Arduino Portenta Machine Control using the Accelstepper Library. When the motor has reached a limit switch, it should stop directly. I was hoping to realize this with an interrupt. So as soon as a "High" signal is present at the limit switch or digital pin 05 (DIN_READ_CH_PIN_05), the function stopmotor() should be called. Unfortunately, this does not happen or does not work. Apparently the function is not even called although a high signal is present at the PIN.
What is also strange is that I have to declare "void stopmotor()" before the setup(), otherwise I cannot compile. That could be the case, but I still find it strange. In any case, I can't get any further. Do any of you have a tip? Or is there another way to stop the stepper motor directly during rotation using a limit switch? I think when stepper.runToPosition() is running only an interrupt can stop it.

#include <Arduino.h>
#include <Arduino_PortentaMachineControl.h> 
#include <pinDefinitions.h> 
#include <AccelStepper.h> 
#include <Wire.h>

#define motorInterfaceType 1

volatile bool runallowed = true; 

AccelStepper stepper = AccelStepper(motorInterfaceType, PinNameToIndex(MC_DO_DO0_PIN), PinNameToIndex(MC_DO_DO1_PIN));

void stopmotor() 
{
  runallowed = false; 

  stepper.setCurrentPosition(0); 
  Serial.println("STOP");       
  stepper.stop();                
  stepper.disableOutputs();      
}

void setup()
{
  Serial.begin(9600); 
  
  Wire.begin();
  if (!MachineControl_DigitalInputs.begin())
  {
    Serial.println("Failed to initialize the digital input GPIO expander!");
  }
  MachineControl_DigitalOutputs.begin();

  attachInterrupt(digitalPinToInterrupt(DIN_READ_CH_PIN_05), stopmotor, RISING);

  stepper.enableOutputs();
  stepper.setMinPulseWidth(130); 
  stepper.setAcceleration(5000); 
  stepper.setMaxSpeed(3200);
}


void loop()
{
  if (runallowed == true)
  {
        stepper.moveTo(16000);    
        stepper.runToPosition(); 
		Serial.println("Rotation reached to 180°");
        delay(10000);
   }
 
}
2

For sure you should not use interrupts like that. "runallowed = false;" should be the only thing there. You don't put serialwrites and some library calls in interrupt, you have to handle those in your loop.

3

Thanks for the tip, I have now given up with the interrupt for the reasons and have realized it via a while loop in the loop(). The runToPosition() function of the accel stepper simply calls the run() function in a while loop anyway.