programing error!!! HELP

Projects Programming
1

i have a problem whith coding!
i start make a security system
and i have a problem to codes!!

const int sensor1Pin = A1; //|---------|
const int sensor2Pin = A2; //|sensors |
const int sensor3Pin = A3; //|pins |
const int sensor4Pin = A4; //|_________|
const int lockPin = A0; //lock pin
const int alertPin = 8; //allert pin
const int indicatorPin = 13; //lock indicator

void setup() {
pinMode(sensor1Pin, INPUT);
pinMode(sensor2Pin, INPUT);
pinMode(sensor3Pin, INPUT);
pinMode(sensor4Pin, INPUT);
pinMode(lockPin, INPUT);
}
void loop() {
if (sensor1Pin, HIGH);
(sensor2Pin, HIGH);
(sensor3Pin, HIGH);
(sensor4Pin, HIGH);
{
digitalWrite(alertPin, LOW);
}else{
digitalWrite(alertPin, HIGH);
}
}

this is the code
and when i press the verify
it tells me an error

alarm.ino: In function 'void loop()':
alarm:25: error: 'else' without a previous 'if'

what i do wrong?PLEASE HELP ME!

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2 
if   (sensor1Pin, HIGH);
     (sensor2Pin, HIGH);
     (sensor3Pin, HIGH);
     (sensor4Pin, HIGH);
{
  digitalWrite(alertPin, LOW);
}else{
  digitalWrite(alertPin, HIGH);
 }

Ifyouquitjammingeverythingtogether, and always used curly braces after the if statements, you'd see that your code looked like:

  if(sensor1Pin, HIGH);
  {
     (sensor2Pin, HIGH);
     (sensor3Pin, HIGH);
     (sensor4Pin, HIGH);
  }
  {
    digitalWrite(alertPin, LOW);
  }
  else
  {
    digitalWrite(alertPin, HIGH);
  }

And, of course, you can see that that is crap.

if statements do NOT end with a semicolon. The comma operator is being misused. The three statements in the if block don't make any sense.

3

Guessing at what you're trying to do, you will need to take a look at digitalRead. You appear to be making the common assumption that the Sensorpin variable holds the state of the pin. It doesn't. Also, look at the comparison operator == .Try getting it to work with one sensor only to start with.

4

Use the auto format option of the IDE. It shows up miss {}, and it helps shows you the real flow of logic in your program.

Mark

5

i have 4 sensors

i mean this code:
"if one of the sensors stop sending votalge
then alert me else dont alert me"
to arduino code.

6

i mean this code:
"if one of the sensors stop sending votalge
then alert me else dont alert me"

Are the sensors analog sensors or digital sensors?

7

PaulS:

i mean this code:
"if one of the sensors stop sending votalge
then alert me else dont alert me"

Are the sensors analog sensors or digital sensors?

analog sensors

8 
if(analogRead(sensor1Pin) < threshold ||
    analogRead(sensor2Pin) < threshold ||
    analogRead(sensor3Pin) < threshold ||
    analogRead(sensor4Pin) < threshold)
{
   // Low voltage on one of the pins
}
else
{
   // All the pins are seeing some voltage
}
9

yes i mean this
but it still showing this problem:

alarm.ino: In function 'void loop()':
alarm:26: error: 'else' without a previous 'if'

10

xitosman:
yes i mean this
but it still showing this problem:

alarm.ino: In function 'void loop()':
alarm:26: error: 'else' without a previous 'if'

So you've made modifications to the code. The new code now has a new error, but you're not going to show us the new code?