Raspberry Pi Pinout

BCM 1 (HAT EEPROM i2c Clock)

Alt0Alt1Alt2Alt3Alt4Alt5
I2C0 SCLSMI SA4DPI DENAVEOUT DSYNCAVEIN DSYNC
  • Physical pin 28
  • BCM pin 1
  • Wiring Pi pin 31

These pins are generally reserved for i2c communication with an EEPROM.

Connect those pins for auto configuration, if the board provides the feature (check the board description for details of EEPROM functionality).