switch case newb

Projects Programming
1

never used a switch case statement before I basically want to increase a PWM value with a button press. however im getting a error. the example code in the IDE wasn't helpful to me.

 if (dimmerPin==LOW);{
    delay(10);
    count++;
      if (count = 4);{
        count = 0;
      }
  }
   switch 
    case count = 0
      dimmerVal = 64;
      break;
    case count = 1:   
      dimmerVal = 128;
      break;
    case count = 2:    
      dimmerVal = 192;
      break;
    case count = 3:
      dimmerVal = 255;
2

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3

The correct syntax for switch can be found here.

4

Once you get the switch case syntax correct you won't be doing much switching until you fix these two errors.

[code]if (count = 4);{
5

cattledog:
Once you get the switch case syntax correct you won't be doing much switching until you fix these two errors.

[code]if (count = 4);{

And this oneif (dimmerPin==LOW);{

6

DKWatson:
The correct syntax for switch can be found here.

Thank you, new code compiles with no errors

7 
int count;
int dimmerVal;
int ledPin = 0;    //analogWrite
int dimmerPin =3;  //digitalRead
int lightPin = 2;  //analogRead
int auxPin = 4;    // digitalWrite


void setup() {
  // put your setup code here, to run once:
  pinMode(dimmerPin,INPUT);
  pinMode(lightPin,INPUT);
  pinMode(ledPin,OUTPUT);
  pinMode(auxPin,OUTPUT);

  count = 3;
  
}

void loop() {
  // put your main code here, to run repeatedly:

  if (dimmerPin,LOW);{
    delay(25);
    count++;
      if (count == 4);{
        count = 0;
      }
  }
   switch (count){
    case 0: 
      dimmerVal = 0;
      break;
    case 1:   
      dimmerVal = 85;
      break;
    case 2:    
      dimmerVal = 170;
      break;
    case 3:
      dimmerVal = 255;
      break;  
}
}
8

if (dimmerPin,LOW)

No, the comma operator is not what you want there.

I think you meant

if (digitalRead(dimmerPin)==LOW)

You must read the pin, and then check the value you get.

Since LOW is just #defined to 0, you can also do

if(!digitalRead(dimmerPin))

But that's not best practice, as it makes the code a bit less readable for no particular benefit.

9

DrAzzy:
if (dimmerPin,LOW)

No, the comma operator is not what you want there.

I think you meant

if (digitalRead(dimmerPin)==LOW)

You must read the pin, and then check the value you get.

Since LOW is just #defined to 0, you can also do

if(!digitalRead(dimmerPin))

But that's not best practice, as it makes the code a bit less readable for no particular benefit.

good call.

10

It may compile without errors, but this is still not going to do what you want it to...

if (dimmerPin,LOW);{

Regards,
Ray L.

11

RayLivingston:
It may compile without errors, but this is still not going to do what you want it to...

if (dimmerPin,LOW);{

Regards,
Ray L.

yes thank you, it has been corrected. sometimes I get in a hurry and forget the little things.
I did grasp the idea of how to set up a switch case, which was my original predicament

12

LandonW:
yes thank you, it has been corrected. sometimes I get in a hurry and forget the little things.
I did grasp the idea of how to set up a switch case, which was my original predicament

Did you also note that the ; does NOT belong in that statement?