This guide explains how to activate GPIOzero and I2C pins in Raspberry Pi 3b with Ubuntu 18.04.3 server arm64. Is recommended to use the following image: http://cdimage.ubuntu.com/releases/bionic/release/ubuntu-18.04.3-preinstalled-server-arm64+raspi3.img.xz. That image contains Ubuntu 18.04.3 server for arm64 and have been tested in Raspberry Pi 3b.

This section is based on the following link: https://wiki.ubuntu.com/ARM/RaspberryPi#Packages

  sudo add-apt-repository ppa:ubuntu-raspi2/ppa
 
  sudo apt update
 
  sudo apt install python3-pip
 
  sudo apt install linux-firmware-raspi2 linux-raspi2 u-boot-rpi flash-kernel

The following packages are optional:

sudo apt install libraspberrypi-bin libraspberrypi-bin-nonfree xserver-xorg-video-fbturbo hello-dkms

This section is mandatory:

  sudo groupadd -f --system gpio
  sudo groupadd -f --system i2c
  sudo groupadd -f --system input
  sudo groupadd -f --system spi

Some important dependences:

This dependencies are really important to run python codes:

  sudo pip3 install smbus
 
  sudo pip3 install gpiozero
 
  sudo pip3 install pigpio
 
  sudo apt install rpi.gpio

Is necessary to create some configuration files:

  sudo touch /etc/modprobe.d/raspi-blacklist.conf
  emacs /etc/modprobe.d/raspi-blacklist.conf

Fill file with the following information:

  # blacklist spi and i2c by default (many users don't need them)
 
  blacklist spi-bcm2708
  blacklist i2c-bcm2708

For the second file, called /etc/modules, add at the end of the file this lines and should look like this:

  # /etc/modules: kernel modules to load at boot time.
  #
  # This file contains the names of kernel modules that should be loaded
  # at boot time, one per line. Lines beginning with "#" are ignored.
 
  snd-bcm2835
  i2c-dev

Then, run the following commands:

  sudo apt  install i2c-tools
  sudo apt  install python-smbus
  sudo adduser pi i2c
  sudo reboot

You can run sudo i2cdetect -y 0, to verify the address of your dispositive already connected to your Raspberry Pi.