Do I have to use the default SPI/I2C/UART pins when connecting modules to my board?
No, you don't have to use the default SPI, I2C and UART pins marked on the pinout card and board header labels.
3 docs tagged with "pins"
View all tagsI followed a learn guide and it's not working on my board
If the learn guide and code was written to run on a specific board, the code could be using pin numbers or names that don't exist on your board.
Why are there no I2S pins marked on the pinout cards?
Like most peripherals on the ESP32, you can use almost any free IO on the headers as I2S pins. Because of this fact, marking specific pins on the pinout cards doesn't make a lot of sense.