Related area

RGB LED, Blink example

Hardware specification

C3, S3, dev boards with RGB LED

Is your feature request related to a problem?

No issue found

Describe the solution you'd like

Implement LED_BUILTIN constant for dev boards with RGB LED. Where not applicable print a helpful error message - for example, This board does not have builtin LED instead of default error: 'LED_BUILTIN' was not declared in this scope
For boards with RGB LED overload function void digitalWrite(uint8_t pin, uint8_t val) to activate the RGB LED via the appropriate driver.
Sample use of overloaded function:

digitalWrite(LED_BUILTIN, HIGH); // RGB turns full white
digitalWrite(LED_BUILTIN, LOW); // RGB turns off

// Nice to have (1) - ability to control each channel
digitalWrite(RED_LED_BUILTIN, HIGH); // Red channel full brightness
digitalWrite(GREEN_LED_BUILTIN, HIGH); // Green channel full brightness
digitalWrite(BLUE_LED_BUILTIN, HIGH); // Blue channel full brightness
// Similar for LOW -> channel is off

// Nice to have (2) - ability to control brightness
digitalWrite(RED_LED_BUILTIN, 128); // Red channel turns on to 50% brightness

Describe alternatives you've considered

No response

Additional context

No response

I have checked existing list of Feature requests and the Contribution Guide

• I confirm I have checked existing list of Feature requests and Contribution Guide.