Defining PB5.

Using Arduino Programming Questions
1

I get the error "PB5 was not declared in this scope". This is my code:

#define LED PB5 // LED is on Pin 13 or Pin 5 of Port B

int main(void) {
	for(;;) {
		PORTB |= (1 << LED);
	}
	return 0; // never reached
}

What is the problem? Thanks.

2

What is the problem? Thanks.

It says right there:

"PB5 was not declared in this scope".

3

But I do write:

#define LED PB5

How could I fix it? Thanks.

4 
#define PB5 5
#define LED PB5
5

#define LED 5 would be shorter :slight_smile:

6 
#define LED PB5

That defines LED as PB5 but it doesn't define PB5, which is what your compiler is complaining about.

7

PB5 should already be defined as '5' through Arduino.h, which gets added automatically to all sketches. Arduino.h actually includes the files like io.h, ioxxxx.h, which actually defines PB5 as 5 and portpins.h, which defines PORTB5 as PB5.

8

Mister_Transistor:
PB5 should already be defined as '5' through Arduino.h, which gets added automatically to all sketches.

Might that depend on the IDE version?

9

OP's code compiles without error on my system. How are you compiling it? is it in a library? Are you using a non-arduino toolchain?

10

The correct symbol is "PORTB5" not "PB5".

Either deliberately or by mistake some AVR Libc versions also include the symbol "PB5".