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Error: "[int variab...
 
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Error: "[int variable] was not declared in this scope"


(@karol)
Active Member
Joined: 1 month ago
Posts: 8
Topic starter  

I defined variables in the void () setup section:

int PumpPin=13;

In the loop section:

digitalWrite(PumpPin,HIGH);

Compilation error: 'PumpPin' was not declared in this scope


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 Hans
(@hans)
Noble Member Admin
Joined: 8 years ago
Posts: 1832
 

Hi Karol,

unfortunately, without the rest of the code, I cannot determine what the issue may be. Where in the code did you define PumpPin?

Since the declaration of PumpPin seems correct, it probably is a matter of scope  - meaning: the variable is unknown in the loop.

This can happen when you declare the variable (for example) in another function, for example in setup().
If that is the case then the variable will not be known in "loop".

As an illustration, just in case you're not very familiar with the scope of variables;

int A=13;

void setup() {
  int B=13;
  ...
}

void loop() {
  int C=13;
  ...
}

 

The variable "A" is defined outside of the functions, therefor know within the functions.
However, the variable "B" is only available in the "setup" function, whereas the variable "C" is only known in the "loop" function.


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(@karol)
Active Member
Joined: 1 month ago
Posts: 8
Topic starter  

Great, thanks Hans, i will try.

And you also showed me how to write a post (the code in special format).


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 Hans
(@hans)
Noble Member Admin
Joined: 8 years ago
Posts: 1832
 

You're welcome, and please let me know if it worked 😉 


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