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[on:]

Me and my friend don't know how to fix this error, or why it's accouring.
Our code looks like this:


const int buttonPin = 2;
const int hl = 3;
int buttonState = 0;
void setup() {
pinMode(hl, OUTPUT);

pinMode(buttonPin, INPUT);
}
void loop(){

buttonState = digitalRead(buttonPin);
if (buttonState == HIGH) {
// turn LED on:
digitalWrite(hl, LOW);
}
else {
// turn LED off:
digitalWrite(hl, HIGH);
}
}
{
digitalWrite(hl, HIGH)
delay(1000);
digitalWrite(hl, low)
delay(1000)
}

When we try to verify it, we get the error:
Button:57: error: expected unqualified-id before '{' token

Please tell us how to fix the problem!!

[Reply #1 on:]

Hello and welcome

You have few problems on the last lines:

- First you forgot some ';'

- Then if you check the count of '{' and '}' (and if you indented your code correctly) then you will see the last lines are outside of void loop().


Here is your code, exactly the same but correctly indented:

Code:

const int buttonPin = 2;
const int hl = 3;
int buttonState = 0;

void setup()
{
  pinMode(hl, OUTPUT);
  pinMode(buttonPin, INPUT);
}

void loop()
{
  buttonState = digitalRead(buttonPin);
  if (buttonState == HIGH)
  {
    // turn LED on:
    digitalWrite(hl, LOW);
  }
  else
  {
    // turn LED off:
    digitalWrite(hl, HIGH);
  }
}

{
  digitalWrite(hl, HIGH)
  delay(1000);
  digitalWrite(hl, low)
  delay(1000)
}

See the problem(s) ??

[Reply #2 on:]

Hi, thanks for the help, we tried to look at it again, but the error is still not fixed, maybe I don't really get what the error is. It comes with the same error when we try to put the '{' other places.

Please help.

[Reply #3 on:]

Me and my friend don't know how to fix this error, or why it's accouring (we have very little experience with programming).
Our code looks like this:


const int buttonPin = 2;
const int hl = 3;
int buttonState = 0;
void setup() {
pinMode(hl, OUTPUT);

pinMode(buttonPin, INPUT);
}
void loop(){

buttonState = digitalRead(buttonPin);
if (buttonState == HIGH) {
// turn LED on:
digitalWrite(hl, LOW);
}
else {
// turn LED off:
digitalWrite(hl, HIGH);
}
}
{
digitalWrite(hl, HIGH);
delay(1000);
digitalWrite(hl, LOW);
delay(1000);
}

When we try to verify it, we get the error:
Button:57: error: expected unqualified-id before '{' token

Please tell us how to fix the problem!!

[Reply #4 on:]

You must have an equal number of braces both { and }.

The braces must enclose blocks of code.
The braces in that code are all over the place.

[Reply #5 on:]

I imagine that this is what you want, but I am not sure.

Code:

const int buttonPin = 2;
const int hl = 3;
int buttonState = 0;
void setup() {
pinMode(hl, OUTPUT);

pinMode(buttonPin, INPUT);
}
void loop(){

buttonState = digitalRead(buttonPin);
if (buttonState == HIGH) {
// turn LED on:
digitalWrite(hl, LOW);
}
else {
// turn LED off:
digitalWrite(hl, HIGH);
}

digitalWrite(hl, HIGH);
delay(1000);
digitalWrite(hl, LOW);
delay(1000);
}

[Reply #6 on:]

First, if you post please use the # button to tag code correctly

Give this a try, I removed a { and added an extra delay(200) , .. (code not tested)

Code:

const int buttonPin = 2;
const int hl = 3;
int buttonState = 0;

void setup()
{
  pinMode(hl, OUTPUT);
  pinMode(buttonPin, INPUT);
}

void loop()
{
  buttonState = digitalRead(buttonPin);
  if (buttonState == HIGH)
  {
    digitalWrite(hl, LOW);
  }
  else
  {
    digitalWrite(hl, HIGH);
  }
  delay(200);  // extra

  digitalWrite(hl, HIGH);
  delay(1000);

  digitalWrite(hl, LOW);
  delay(1000);
}

[Reply #7 on:]

Problem 1 - all the statements should end with a semi-colon like this

Code:

    digitalWrite(hl, HIGH);

Are there any lines in your sketch that don't ?

Problem 2 - when, if ever, is this code going to be executed ?

Code:

{
  digitalWrite(hl, HIGH)
  delay(1000);
  digitalWrite(hl, low)
  delay(1000)
}

[Reply #8 on:]

First, if you post please use the # button to tag code correctly

Give this a try, I removed a { and added an extra delay(200) , .. (code not tested)

Code:

const int buttonPin = 2;
const int hl = 3;
int buttonState = 0;

void setup()
{
  pinMode(hl, OUTPUT);
  pinMode(buttonPin, INPUT);
}

void loop()
{
  buttonState = digitalRead(buttonPin);
  if (buttonState == HIGH)
  {
    digitalWrite(hl, LOW);
  }
  else
  {
    digitalWrite(hl, HIGH);
  }
  delay(200);  // extra

  digitalWrite(hl, HIGH);
  delay(1000);

  digitalWrite(hl, LOW);
  delay(1000);
}

Hi, it worked, thanks, but why did you make an extra delay, and why did it work???

[Reply #9 on:]

Please don't cross post. Threads merged.

[Reply #10 on:]

Hi, it worked, thanks, but why did you make an extra delay, and why did it work???

That is your homework:)
Follow the code by hand, read it carefully line by line.
Be the Arduino !
and do what the code says and you will understand.

[Reply #11 on:]

Follow the code by hand, read it carefully line by line.
Be the Arduino !
and do what the code says and you will understand.

Well, ok, thank you!