arduino-esp32/variants/metro_esp-32/pins_arduino.h

#ifndef Pins_Arduino_h
#define Pins_Arduino_h

#include <stdint.h>

#define EXTERNAL_NUM_INTERRUPTS 16
#define NUM_DIGITAL_PINS        40
#define NUM_ANALOG_INPUTS       16

#define analogInputToDigitalPin(p)  (((p)<20)?(esp32_adc2gpio[(p)]):-1)
#define digitalPinToInterrupt(p)    (((p)<40)?(p):-1)
#define digitalPinHasPWM(p)         (p < 34)

static const uint8_t LED_BUILTIN = 2;
#define BUILTIN_LED  LED_BUILTIN // backward compatibility
#define LED_BUILTIN LED_BUILTIN

static const uint8_t KEY_BUILTIN = 0;

static const uint8_t SDA = 21;
static const uint8_t SCL = 22;

static const uint8_t ADR = 12;

#endif /* Pins_Arduino_h */