Expected initializer before 'while'

Projects Programming
1

I am having trouble. It keeps saying missing initializer before 'while' and when I add { before while it says you cannot add something before { so I add loop after { and it still doesn't work. Here is the code.

#include <Servo.h>

Servo myservo;  // create servo object to control a servo
Servo myservo2; // create servo object to control a servo
Servo myservo3; // create servo object to control a servo
Servo myservo4; // create servo object to control a servo
Servo myservo5; // create servo object to control a servo
int servoPin = 9;// this pin must be of those with PWM ~
int servoPin2 = 10;
int servoPin3 = 11; 
int servoPin4 = 3;
int servoPin5 = 6;
int pushButtonPin =2;// the pin where push button is connected
int pushButtonPin2 =4;
int pushButtonPin3 =13;
int pushButtonPin4 =8;
int pushButtonPin5 =7;
  
int angle =25;    // initial angle  for servo
int angleStep =5;

void setup() {
  // Servo button demo by Robojax.com
  Serial.begin(9600);          //  setup serial
  myservo.attach(servoPin); // attaches the servo on pin 9 to the servo object
  myservo2.attach(servoPin2);
  myservo3.attach(servoPin3);
  myservo4.attach(servoPin4);
  myservo5.attach(servoPin5);  
  pinMode(pushButtonPin,INPUT_PULLUP);
  pinMode(pushButtonPin2,INPUT_PULLUP);
  pinMode(pushButtonPin3,INPUT_PULLUP);
  pinMode(pushButtonPin4,INPUT_PULLUP);
  pinMode(pushButtonPin5,INPUT_PULLUP);
  Serial.println("Robojax Servo Button ");
   //Full video details: https://youtu.be/qJebLpzLE24
}

void loop() {
  while(digitalRead(pushButtonPin) == LOW){
  // 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 <= 0 || angle >= 180) {
      angleStep = -angleStep;
    }
    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
  }
  
  void loop() {
    while(digitalRead(pushButtonPin2) == LOW){
  // 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 <= 0 || angle >= 180) {
      angleStep = -angleStep;
    }
    myservo2.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
  }// while
}
2

Hi guys its been 5 minutes and I found the answer!! No need to answer anymore, I don't know how to close the question. I just forgot to add ; basic syntax everyone needs to know lol. Im so dumb, but ty

3

Mark the topic as solved.

Also please take care where you post questions in future. Each forum section has a sticky post at the top describing what kinds of topics the section is intended for.

4

You have got two loop()s.
That can't be right.

5

For the benefit of others, please post the correct sketch in a new reply and explain what was wrong

6

Hi how do I mark the post solved?

7

Below each reply there is a checkbox that allows you to mark that reply as having solved your problem

8

okay thank you

9

What was wrong is the syntax. I forgot to put ';' at the end of void loop.

10

how so? I am supposed to have 5 buttons and 5 servo each button making a servo move so there must be 5 void loops in total. How is it wrong? (I am still new so please explain)

11

Sorry, but I don't understand what you mean by that. Please post the full corrected sketch

12

There was no ; after void loop like this.

void loop() ; {
    while(digitalRead(pushButtonPin2) == LOW){
  // 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 <= 0 || angle >= 180) {
      angleStep = -angleStep;
    }
13

No, that's wrong. I don't know what you think you have solved, but that isn't it. Putting a semicolon there would cause compilation errors.

void loop();

would be interpreted as a forward declaration. The code inside the { } following it would not be allowed outside a function.

14

As @PaulRB has pointed out that is wrong so you have not fixed anything I am afraid

15

As far as I know, an Arduino sketch must have:

  • ONE setup() function
  • ONE loop() function
1 Like
16

can you help me figure it out please then as you are correct I am having difficulties closing off the code.

17

Start here. @JohnLincoln is right. You may have other functions called whatever you name them, but you will always only have ONE each void setup() and void loop().

Here's a start to correcting your code:

#include <Servo.h>

Servo myservo;  // create servo object to control a servo
Servo myservo2; // create servo object to control a servo
Servo myservo3; // create servo object to control a servo
Servo myservo4; // create servo object to control a servo
Servo myservo5; // create servo object to control a servo
int servoPin = 9;// this pin must be of those with PWM ~
int servoPin2 = 10;
int servoPin3 = 11;
int servoPin4 = 3;
int servoPin5 = 6;
int pushButtonPin = 2; // the pin where push button is connected
int pushButtonPin2 = 4;
int pushButtonPin3 = 13;
int pushButtonPin4 = 8;
int pushButtonPin5 = 7;

int angle = 25;   // initial angle  for servo
int angleStep = 5;

void setup() {
  // Servo button demo by Robojax.com
  Serial.begin(9600);          //  setup serial
  myservo.attach(servoPin); // attaches the servo on pin 9 to the servo object
  myservo2.attach(servoPin2);
  myservo3.attach(servoPin3);
  myservo4.attach(servoPin4);
  myservo5.attach(servoPin5);
  pinMode(pushButtonPin, INPUT_PULLUP);
  pinMode(pushButtonPin2, INPUT_PULLUP);
  pinMode(pushButtonPin3, INPUT_PULLUP);
  pinMode(pushButtonPin4, INPUT_PULLUP);
  pinMode(pushButtonPin5, INPUT_PULLUP);
  Serial.println("Robojax Servo Button ");
  //Full video details: https://youtu.be/qJebLpzLE24
}

void loop() {
  int pushButtonState = digitalRead(pushButtonPin);
  while (pushButtonState == LOW) {
    // 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 <= 0 || angle >= 180) {
      angleStep = -angleStep;
    }
    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
  }
}

Note the way we read pushbuttons:

int pushButtonState = digitalRead(pushButtonPin);

Why? The way you had it will read (and print) only the Arduino pin number you assigned to button to.

18

Thank you

19

Thank you so much! Sorry I am still new I am learning

20

So after

delay(100); //waits for the servo to get there
  }

// new button and servo?