Limit switch with stepper

Projects General Guidance
1

I am having a lot of issues on this project for my brother, basically we have a pocket door in his basement to his "man cave". We have tied a stepper motor to the door with a timing belt. At each end of the door opening is a limit switch, one for CLOSED position and OPEN position. He wants a RFID scanner on the outside to open it, and a push button on the inside that will close or open the door. After the door is opening from inside or outside, after a few seconds the door closes automatically. the motor has an acceleration coded in, but the number of steps to the OPEN/CLOSED positions aren't the same, so limit switches with do a quick stop for the motor. I hope this makes sense. hope we can find a solution, my code gets stuck, it'll open the door but won't stop at the limit switch and won't leave that section of code. we also have a push button in place of the RFID for a temporary set up

#include "SPI.h"
#include "MFRC522.h"
#include <AccelStepper.h>
#define SS_PIN 9
#define RST_PIN 8
#define dirPin 2
#define stepPin 3
#define motorInterfaceType 1
MFRC522 rfid(SS_PIN, RST_PIN);
MFRC522::MIFARE_Key key;
AccelStepper stepper = AccelStepper(motorInterfaceType, stepPin, dirPin);
int limit1;
int limit2;
int debounce = 200;
int enable;
int wiperRelay = 16;
int redButton = 20;
int doorButton;
int limit1State = 0;
int limit2State = 0;
int redButtonState = 0;
int doorButtonState = 0;
int elapsedTime = 10000;

void setup() {
  stepper.setMaxSpeed(1000000);
  stepper.setAcceleration(6000);
  delay(1000);
  Serial.begin(9600);
  SPI.begin();
  rfid.PCD_Init();
  pinMode(limit1, INPUT);
  pinMode(limit2, INPUT);
  pinMode(wiperRelay, OUTPUT);
  pinMode(redButton, INPUT);
  pinMode(doorButton, INPUT);
}

void loop() {
  if (!rfid.PICC_IsNewCardPresent() || !rfid.PICC_ReadCardSerial()) {
    return;

    // Serial.print(F("PICC type: "));
    MFRC522::PICC_Type piccType = rfid.PICC_GetType(rfid.uid.sak);
    // Serial.println(rfid.PICC_GetTypeName(piccType));

    // Check is the PICC of Classic MIFARE type
    if (piccType != MFRC522::PICC_TYPE_MIFARE_MINI &&
        piccType != MFRC522::PICC_TYPE_MIFARE_1K &&
        piccType != MFRC522::PICC_TYPE_MIFARE_4K) {
      Serial.println(F("Your tag is not of type MIFARE Classic."));
      return;
    }
    String strID = "";
    for (byte i = 0; i < 4; i++) {
      strID +=
        (rfid.uid.uidByte[i] < 0x10 ? "0" : "") +
        String(rfid.uid.uidByte[i], HEX) +
        (i != 3 ? ":" : "");
    }

    strID.toUpperCase();
    Serial.print("Tap card key: ");
    Serial.println(strID);
    delay(1000);

    if (strID.indexOf("20:CC:6F:85") >= 0) {  //put your own tap card key;
      Serial.println("********************");
      Serial.println("**Authorised access**");
      Serial.println("********************");
      DoorAccess;
      return;
    }
    else {
      Serial.println("****************");
      Serial.println("**Access denied**");
      Serial.println("****************");
      !DoorAccess;
      return;
    }
  }

  redButtonState = digitalRead(redButton);
  if (redButtonState == HIGH) {
    digitalWrite(wiperRelay, LOW);
    delay(100);
    digitalWrite(wiperRelay, HIGH);
    DoorAccess;
  } else {
    // turn LED off:
    digitalWrite(wiperRelay, HIGH);
  }


  doorButtonState = digitalRead(doorButton);
  if (doorButtonState == HIGH > debounce) {
    DoorAccess;
  }

  limit2State = digitalRead(limit2);
  if (limit2State == HIGH > elapsedTime) {
    DoorAccess;
  }

}
void DoorAccess() {
  limit1State = digitalRead(limit1);
  if (limit1State == HIGH > debounce) {
    enable = LOW;
    Serial.println("Door opening");
    stepper.moveTo(60000);
    stepper.runToPosition();
    limit2State = digitalRead(limit2);
    while (limit2State == HIGH > debounce) {
      stepper.stop();
      stepper.runToPosition();
      enable = HIGH;
      Serial.println("Door opened");
    }

  }
  else if (limit2 == HIGH > debounce) {
    enable = LOW;
    Serial.println("Door closing");
    stepper.moveTo(-60000);
    stepper.runToPosition();
    while (limit1 == HIGH > debounce) {
      stepper.stop();
      stepper.runToPosition();
      enable = HIGH;
      Serial.println("Door closed");
    }
  }
}
2

I've added random serial prints in the code to see in the monitor where my code goes and gets stuck.

#include "SPI.h"
#include "MFRC522.h"
#include <AccelStepper.h>
#define SS_PIN 9
#define RST_PIN 8
#define dirPin 15
#define stepPin 14
#define motorInterfaceType 1
AccelStepper stepper = AccelStepper(motorInterfaceType, stepPin, dirPin);
const int doorButton = 19;
const int limit1 = 18;
const int limit2 = 17;
const int enable = 23;
int limit1State;
int limit2State;
int doorButtonState;
int lastDoorButtonState = LOW;
int lastlimit1State = LOW;
int lastlimit2State = LOW;
unsigned long lastDoorDebounceTime = 0;
unsigned long lastlimit1Time = 0;
unsigned long lastlimit2Time = 0;
unsigned long debounceDelay = 50;
unsigned long limit1Delay = 50;
unsigned long limit2Delay = 50;

void setup() {
  stepper.setMaxSpeed(1000000);
  stepper.setAcceleration(6000);
  pinMode(doorButton, INPUT);
  pinMode(limit1, INPUT);
  pinMode(limit2, INPUT);
  pinMode(enable, OUTPUT);
  digitalWrite(enable, HIGH);
  Serial.begin(9600);
}

void loop() {
  Serial.println("1");
  int doorReading = digitalRead(doorButton);
  
  Serial.println("2");
  
  if (doorReading != lastDoorButtonState) {
    lastDoorDebounceTime = millis();
  }

    Serial.println("3");
    
  if ((millis() - lastDoorDebounceTime) > debounceDelay) {
    if (doorReading != doorButtonState) {
      doorButtonState = doorReading;
      if (doorButtonState == HIGH) {
        int limit1Reading = digitalRead(limit1);
        int limit2Reading = digitalRead(limit2);
        if (limit1Reading != lastlimit1State) {
          lastlimit1Time = millis();

            Serial.println("4");
            
        }
        if ((millis() - lastlimit1Time) > limit1Delay) {
          if (limit1Reading != limit1State) {
            limit1State = limit1Reading;
            if (limit1State == HIGH) {
              digitalWrite(enable, LOW);
              Serial.println("Door opening");
              stepper.moveTo(80000);
              stepper.runToPosition();
              int limit2Reading = digitalRead(limit2);
              if (limit2Reading != lastlimit2State) {
                lastlimit2Time = millis();
                  Serial.println("5");
              }
              if ((millis() - lastlimit2Time) > limit2Delay) {
                  Serial.println("6");
                if (limit2Reading != limit2State) {
                    Serial.println("7");
                  limit2State = limit2Reading;
                  while (limit2State == HIGH) {
                    stepper.stop();
                    stepper.runToPosition();
                    digitalWrite(enable, HIGH);
                      Serial.println("6");
                    Serial.println("Door opened");
                  }
                }
              }
            }
          }
        }
        lastlimit1State = limit1Reading;
        lastlimit2State = limit2Reading;
        if (limit2Reading != lastlimit2State) {
          lastlimit2Time = millis();
        }
        if ((millis() - lastlimit2Time) > limit2Delay) {
          if (limit2Reading != limit2State) {
            limit2State = limit2Reading;
            if (limit2State == HIGH) {
              digitalWrite(enable, LOW);
              Serial.println("Door closing");
              stepper.moveTo(-60000);
              stepper.runToPosition();
              while (limit1Reading != lastlimit1State) {
                lastlimit1Time = millis();
              }
              if ((millis() - lastlimit1Time) > limit1Delay) {
                if (limit1Reading != limit1State) {
                  limit1State = limit1Reading;
                  if (limit1State == HIGH) {
                    stepper.stop();
                    stepper.runToPosition();
                    digitalWrite(enable, HIGH);
                    Serial.println("Door closed");
                  }
                }
              }
            }
          }
        }
        lastlimit1State = limit1Reading;
        lastlimit2State = limit2Reading;
      }
    }
  }
  lastDoorButtonState = doorReading;
}
3

while (limit2State == HIGH)
{
stepper.stop();
stepper.runToPosition();
digitalWrite(enable, HIGH);
Serial.println("6");
Serial.println("Door opened");
}

How you get out of this while loop ?

4

What's the mean of this condition?

5

infinite loop

infinite loop

6

Im very new/rustic at coding, so I was under the impression after if completed the initial reading it exited the loop

7

while (. . . )
{
. . .
}

At the line with the } brace, you go back to while ( . . .)

Only use while( ) loops if you know they will execute very very fast.

8

You keep updating the limit2State value within the while-loop, or use a break statement.

9

so how should I fix this?

10

You put the above line of code inside your "while" loop, so the controlling value is changed.

11

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