Change hardcoded Pin 13 to LED_BUILTIN

[ubidefeo]

No description provided.

[CLAassistant]

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[per1234]

The circuit description comment also needs to be dealt with:

arduino-examples/examples/04.Communication/PhysicalPixel/PhysicalPixel.ino

Line 12 in d62f11c

- LED connected from digital pin 13 to ground through 220 ohm resistor

I'm not sure what the best approach is. The associated tutorial should be considered (of course it can be updated as needed).

Most of the examples are doing the same hardcoded pin 13 thing as this "PhysicalPixel" example was using. The only exceptions which are using LED_BUILTIN:

• Blink (tutorial here)
• BlinkWithoutDelay (tutorial here

Those might serve as a useful model for how to proceed to take advantage of LED_BUILTIN in other examples and tutorials.