Hello @dominik

the nice thing about ESP32 and its variants (like the C3) is that different functions (like SPI) can use almost any GPIOs.

With the Arduino environment you can define the GPIOs to be used for SPI like this:

#define SCK GPIO_NUM_6 #define MISO GPIO_NUM_4 #define MOSI GPIO_NUM_7 #define CS GPIO_NUM_5 SPI.begin(SCK, MISO, MOSI, -1);