Triggering a servo to repeat an action

Using Arduino Project Guidance
1

I am currently working on a project for a pill dispenser. The feeding mechanism works similarly to a gun in that a slide with a slot moves over, a pill drops in from a hopper, and then the slide moves to the dispensing area where the pill drops out of the device. The slide is actuated by a servo that spins to pull the slide to the dispensing position and then retracts back to the hopper to get another pill. I have written some code that allows the system to be triggered by a button, I've included the code below.

I am currently trying to rewrite my code to use a four-position rotary switch so that I can, with a single button press, dispense the desired number of pills. Help with the code and a simple diagram of how your method incorporates the rotary switch would be helpful.

I have used a rotary switch in series with a button in the past resulting in the Arduino effectively recognizing multiple buttons but I am open to new methods.

#include <Servo.h>

Servo myservo;  
#define servoPin 3 //~
#define pushButtonPin 2 

int angle =179;   
int angleStep = 10;
const int minAngle = 0;
const int maxAngle = 180;

const int type =2;

int buttonPushed =0;

void setup() {
  Serial.begin(9600);          //  setup serial
  myservo.attach(servoPin);  // attaches the servo on pin 3 to the servo object
  pinMode(pushButtonPin,INPUT_PULLUP);
   Serial.println("Robojax Servo Button ");
   myservo.write(angle);//initial position
}

void loop() {
  if(digitalRead(pushButtonPin) == LOW){
    buttonPushed = 1;
  }
   if( buttonPushed ){
  // change the angle for next time through the loop:
  angle = angle - angleStep;

    // reverse the direction of the moving at the ends of the angle:
    if (angle <= minAngle) {
      angleStep = -angleStep;
       if(type ==1)
        {
            buttonPushed =0;       
        }
    }

        if (angle >= maxAngle) {
      angleStep = -angleStep;
        if(type ==2)
        {
            buttonPushed =0;                   
        }
    }

    myservo.write(angle); // move the servo to desired angle
      Serial.print("Moved to: ");
      Serial.print(angle);   // print the angle
      Serial.println(" degree");    
  delay(100); // waits for the servo to get there
   }

  
}
2

What does the Serial.print tell?
To make the best presentation use autoformat in the IDE and code tags here when pasting.

3

Thank you for the advice.

I modified another set of code and the serial.print is from that code. I am unsure what it is doing.

4 
    Serial.print("Moved to: ");
    Serial.print(angle);   // print the angle
    Serial.println(" degree");

They print out the variable "angle" assuming You have activated serial monitor in the IDE.

5

Use a rotary encoder to increment/decrement the pill count variable.  Limit the high and low values with code.  Employ the encoder's built-in pushbutton, or a discrete button, to start the dispense cycle.

6

My current difficulty isn't necessarily incorporating a rotary switch. My main issue is how to repeat the dispensing action. The way I have coded it is simply including a <= or >= argument which moves it in the appropriate direction if the angle is between min and max angles.

Is there a way to get the servo to repeat the action easily?

7

A general outline: Gather everything which constitutes the actuation sequence and put it in a finite state machine.

Start with just one button push initiating one cycle.  To finish, put together a loop which counts how many cycles have been done.  If not done continue initiating cycles.

8

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