An Error Where It Shouldn't Be...

Forum 2005-2010 (read only) Software Syntax & Programs
#1

I'm hoping that someone can help me suss this out. I'm getting an error message that, as far as I can tell, shouldn't be there. When the compiler gets to the line in red, it gives me the message " In function 'void setup()': error: expected `)' before ';' token In function 'void loop()':"

define ledAPin 13

define ledBPin 12;

define piezoAPin = 0;

define piezoBPin = 1;

byte valA = 0; byte valB = 0;

int THRESHOLD = 100;

void setup() { pinMode(ledAPin, OUTPUT); pinMode(ledBPin, OUTPUT);

}

void loop() { valA = analogRead(piezoAPin); valB = analogRead(piezoBPin); digitalWrite(ledAPin, LOW); digitalWrite(ledBPin, HIGH);

if (valA >= THRESHOLD) { digitalWrite(ledAPin, HIGH); delay(25); }

if (valB >= THRESHOLD)

{ digitalWrite(ledBPin, HIGH); delay(25); } }

I've spent the last half hour staring at my screen, trying for the life of me to understand why I'm getting the message. I can't.

Many thanks.

#2 
#define ledAPin 13    
#define ledBPin 12;
#define piezoAPin = 0;  
#define piezoBPin = 1;

should look like:

#define ledAPin 13    
#define ledBPin 12
#define piezoAPin 0
#define piezoBPin 1
#3

Ah! Thank you. I knew it was going to be something piddling like that.

#4

Reminds me of the good old days, when compilers actually had error messages like "error at or near line X". :)

-j

#5

Ok, so your sharp eyes helped me with my first problem. I wonder if they could help me with my new one. Basically, what I want to happen is for piezoAPin to turn both leds on. Then piezoBPin turns ledB off on the first hit, and ledA off on the second. I can't seem to figure it out.

Here's what I've got:

define ledAPin 13

define ledBPin 12

define piezoAPin 0

define piezoBPin 1

int valA = 0; int valB = 0;

int THRESHOLD = 100;

void setup() { pinMode(ledAPin, OUTPUT); pinMode(ledBPin, OUTPUT);

}

void loop() { valA = analogRead(piezoAPin); valB = analogRead(piezoBPin);

if (valA >= THRESHOLD) { digitalWrite(ledAPin, HIGH); digitalWrite(ledBPin,HIGH); delay(100); }

if (valB >= THRESHOLD)

{ digitalWrite(ledBPin, LOW); delay(100); }

//* figure out how to get it to turn off ledAPin if and only if ledBPin is LOW *// while (ledBPin == LOW) { if (valB >= THRESHOLD) { digitalWrite(ledBPin, LOW); } }

}

The bit after the comment is where I'm trying to tell it to turn ledA off.

I haven't been able to work out how to do 'if and' statements yet. I want to tell it, 'if ledB is off AND ledA is on, then on piezoB hit, turn ledA off.

If I could make a further request, I'd like to figure out how it works by myself, I'd at least like to write the code. I think my problem is just the way I'm thinking about how to tell the thing what I want it to do.

Thanks muchly again.

#6

Well, this is a little ugly (for me,) but it's about what you want to do. I just hacked it together in a couple of minutes - it compiles, but I didn't test it on an Arduino (I don't have any piezos laying around)

#define ledAPin 13    
#define ledBPin 12
#define piezoAPin 0  
#define piezoBPin 1
#define threshold 100

void setup() 
{
 pinMode(ledAPin, OUTPUT); 
 pinMode(ledBPin, OUTPUT);
}

void loop() {
 if (analogRead(piezoAPin) >= threshold & digitalRead(ledAPin) == LOW & digitalRead(ledBPin) == LOW) {
   digitalWrite(ledAPin, HIGH);
   digitalWrite(ledBPin,HIGH); 
   delay(100);                      
 }

 if (analogRead(piezoBPin) >= threshold) {
   if (digitalRead(ledBPin) == HIGH & digitalRead(ledAPin) == HIGH) { // If they're both on, just turn off one
     digitalWrite(ledBPin, LOW); // Just turn off B
   }
   else if (digitalRead(ledAPin) == HIGH) { // else if A is on, turn it off.
     digitalWrite(ledAPin, LOW); // Turn off A
   }
   delay(100);
 }
}

Basically, the first if statement only turns your LEDs on if piezo A if over the threshold and if the LEDs are already off (this differs from your code a bit - yours always turns the LEDs on whether they're already on or not.)

The second if statement reads the B piezo, and if both LEDs are on, it turns off LED B. Else, if only LED A is lit, then it will turn it off.

#7