Adding new GPIO20 define for Arduino framework

[marius]

I'm testing the new ESP32-Pico-Mini-02 module which features GPIO20 that was previously unavailable. The current version of the Arduino framework doesn't contain definitions for GPIO20 and I'm getting errors like:

Code: Select all

"GPIO_NUM_20" is undefined

Is there an easy way I could define GPIO20 in my current project main.h header file? What is the correct syntax for doing that? This way it would keep existing libraries and code working with the new pin.

Thanks!

[boarchuz]

You might still run into problems if any drivers check the validity of the pin (eg. pinMode(20, OUTPUT) -> error?).

Something like this will make the compiler stop complaining but don't expect correct functionality:
#define GPIO_NUM_20 ((gpio_num_t)(20))

Using a different pin for now would be best.

[marius]

Defining it that way does allow the code to compile fine but as expected I don't get correct functionality, not even a simple blinky with digitalWrite() function.

I have also tried experimenting with modifying ..\tools\sdk\include\driver\driver\gpio.h specifically:
line 59 adding "#define GPIO_SEL_20 (BIT(20))"
line 156 adding "GPIO_NUM_20 = 20,"

But with no luck, I still don't get functionality for writing to that pin.

[boarchuz]

Yeah there's a lot more to it. A lot of the Arduino stuff is precompiled so making changes there won't achieve much.

If you're really motivated and you only need simple IO, you might look at ESP-IDF to learn how to initialise and read/write using the registers directly.

I would pick a different pin!

[marius]

Okay, thanks for the info.