expected ')' before ';' token

Using Arduino Programming Questions
#1

I don’t understand why is it coming again and again.
The error message is always ‘‘expected ‘)’ before ‘;’ token’’.
I don’t get that there is already a ‘)’ before ‘;’ so, why is it saying this over and over again on the last line.
void setup() {
pinMode (A0; OUTPUT); //VCC pin;
pinMode (A1; OUTPUT); //GND pin;
pinMode (A2; INPUT); // receives signal from sensor;
Serial.begin (9600);
}
// the loop routine runs over and over again;
void loop() {
digitalWrite (A0; HIGH);
digitalWrite (A1); LOW);
if () {
(analogRead(CM) < 5);
digitalWrite(8; HIGH); // provide high voltage to digital pin 8;
digitalWrite(9; LOW); //provide low voltage to digital pin 9;
}
}

MYIRSENSOR.ino (467 Bytes)

#2

You seem to have confused semicolons and commas.

digitalWrite (A1); LOW);

Should be like

digitalWrite(A1, LOW);

You also have an if statement whose condition seems to have escaped into the next line. You should look at some example codes and try to learn the syntax.

#3

int CM;
void setup() {
pinMode (A0, OUTPUT); //VCC pin;
pinMode (A1, OUTPUT); //GND pin;
pinMode (A2, INPUT); // receives signal from sensor;
Serial.begin (9600);
}
// the loop routine runs over and over again;
void loop() {
digitalWrite (A0, HIGH);
digitalWrite (A1, LOW);
if (analogRead(CM < 5)){
digitalWrite(8, HIGH); // provide high voltage to digital pin 8;
digitalWrite(9, LOW); //provide low voltage to digital pin 9;
}
}

#4

Pleas use ctrl-T before pasting any code (within code tags) here... it makes things so much more readable....

#5

Hi.
????? Parth_Saini and Saridol

Welcome to the forum.

Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html then look down to item #7 about how to post your code.
It will be formatted in a scrolling window that makes it easier to read.

Thank you.. Tom... :slight_smile:

#6

Hi,
Parth_Saini
You need to look up how the structure of :

pinMode
digitalWrite
analogRead
if

statements, in particular the use of , and ; marks.

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?
This bit

 pinMode (A0; OUTPUT); //VCC pin;
  pinMode (A1; OUTPUT); //GND pin;

worries me.

Thanks… Tom… :slight_smile:

#7

Hi,
Whose posting is this?
????? Parth_Saini and Saridol

Tom.... :slight_smile:

#8 
  if () {
  (analogRead(CM) < 5);

Oops.

#9

@saripdol

 if (analogRead(CM < 5)){

oops.

#10

I don’t understand why this normal thing is not working. I can’t understand why this is always saying expected ‘)’ before ‘;’ token.

int IR_SENSOR_VCC = A2;
int IR_SENSOR_GND = A1;
int IR_SENSOR_OP = A0;
void setup() {
pinMode (IR_SENSOR_VCC, OUTPUT);
pinMode (IR_SENSOR_GND, OUTPUT);
pinMode (IR_SENSOR_OP, INPUT);
Serial.begin (9600);
}
// the loop routine runs over and over again;
void loop() {
digitalWrite (A0, HIGH);
digitalWrite (A1, LOW);
digitalWrite (A2, HIGH);
int duration = pulseIn (IR_SENSOR_OP, HIGH);
int distance = (duration/2)/29.1;
Serial.print (distance);
Serial.println(‘CM’);
if(distance <= 5); (
digitalWrite(8, HIGH); // output high voltage to digital pin 8;
);
else if(distance >= 5); (
digitalWrite(8, LOW); // output low voltage to digital pin 8;
);
}

#11

Because your "if" syntax is wrong in several ways. Do a little Googling ("c if statement") to understand the correct syntax for a c/c++ if/else statement.

The error message gives you the exact line number, and character position of the error...

Regards,
Ray L.

#12

Please don't start new topics when you already have a very similar one open.

#13

This is a good place to start.

#14

Hi,

if(distance <= 5); (
      digitalWrite(8, HIGH); // output high voltage to digital pin 8;
  );
else if(distance >= 5); (
digitalWrite(8, LOW); // output low voltage to digital pin 8;
);

Look up how if statements are constructed. Particularly the use of { } ( ) and ;

Tom… :slight_smile:

#15

Like other members suggested, learn some of the basic syntax of C language.

Try this code, did some changes. Compare the code with yours and see the difference.

int IR_SENSOR_VCC = A2;
int IR_SENSOR_GND = A1;
int IR_SENSOR_OP = A0;
void setup() {
  pinMode (IR_SENSOR_VCC, OUTPUT);
  pinMode (IR_SENSOR_GND, OUTPUT);
  pinMode (IR_SENSOR_OP, INPUT);
  Serial.begin (9600);
}
// the loop routine runs over and over again;
void loop() {
  digitalWrite (A0, HIGH);
  digitalWrite (A1, LOW);
  digitalWrite (A2, HIGH);
  int   duration = pulseIn (IR_SENSOR_OP, HIGH);
  int  distance = (duration / 2) / 29.1;
  Serial.print (distance);
  Serial.println("CM");
  if (distance <= 5) {
    digitalWrite(8, HIGH); // output high voltage to digital pin 8;
  }
  else if (distance >= 5){
    digitalWrite(8, LOW); // output low voltage to digital pin 8;
  }
}
#16 
pinMode (IR_SENSOR_GND, OUTPUT);

As Tom already pointed this, are you going to connect some sensors GND to this pin?

Setting LOW to a pin cant be considered as GND. Use the Arduino GND pin instead.

digitalWrite (A0, HIGH);

do you really need this in the loop? can it be moved to setup()? can the external device directly powered from 5v/3.3v pin of Arduino?

#17

Function arguments are separated by commas, not semicolons.
Strings are delimited by double quotes, not single quotes
Statement-lists are surrounded by braces, not parenthesis.
If statements require a condition - an empty set of parenthesis is not admissable.

#18