OLED Display on Raspberry Pi + Ubunutu Server 21.10

Raspbeery Pi 4b Ubuntu 21.10 OLED.md

Raspberry Pi + Ubuntu Server 21.10 + OLED Display

• Raspberry Pi 4 (8GB)
• Ubuntu Server 21.10 (64-bit server OS for arm64 architectures)
• Mini-tower case with SSD (NVMe M.2)
• 128×64 I2C OLED display

1. Make sure your system is up to date

sudo apt update && sudo apt upgrade -y

Reboot your PI

sudo reboot

2. Install drivers and libraries

sudo apt install -y python3-pip python3-dev python3-pil python3-setuptools python3-rpi.gpio i2c-tools

3. Add your current user account to the group i2c

sudo usermod -aG i2c ubuntu

4. Connect the OLED Display to the Raspberry Pi

5. Check if the display was recognized

i2cdetect -y 1

The output should look like the following:

ubuntu@ubuntu:~$ i2cdetect -y 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:                         -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- 3c -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
ubuntu@ubuntu:~$

6. Install SSD1306 python libary

sudo pip3 install adafruit-circuitpython-ssd1306

7. Install monitor script

Clone the script from Michael Klements

git clone https://github.com/mklements/OLED_Stats.git

Go to the cloned directory

cd OLED_Stats

Then run the script by entering:

python3 stats.py

If you have the following error when you execute the script:

ubuntu@ubuntu:~/OLED_Stats$ python3 stats.py
Traceback (most recent call last):
  File "/home/ubuntu/OLED_Stats/stats.py", line 16, in <module>
    oled_reset = digitalio.DigitalInOut(board.D4)
  File "/usr/local/lib/python3.9/dist-packages/digitalio.py", line 145, in __init__
    self.direction = Direction.INPUT
  File "/usr/local/lib/python3.9/dist-packages/digitalio.py", line 175, in direction
    self._pin.init(mode=Pin.IN)
  File "/usr/local/lib/python3.9/dist-packages/adafruit_blinka/microcontroller/bcm283x/pin.py", line 37, in init
    GPIO.setup(self.id, GPIO.IN)
RuntimeError: Not running on a RPi!
ubuntu@ubuntu:~/OLED_Stats$

Pay attention to the last line! It means that you have a persmission problem. There are two methods to solve this issue:

Method 1. Run the script with elevated privileges:

sudo python3 stats.py

Method 2. Make sure the current user has the proper privileges.

With Ubuntu server 21.10 64-bit on RPi 4, that can be achieved by creating a gpio group, and adding an udev rule to give this group access to /dev/gpiomem (which can normally only be accessed by root).

Create a /etc/udev/rules.d/90-gpio.rules file

sudoedit /etc/udev/rules.d/90-gpio.rules

add the following content

KERNEL=="gpiomem", OWNER="root", GROUP="gpio"

Create the group gpio and assign it to an existing user, in my case "ubuntu":

sudo groupadd -f --system gpio
sudo usermod -a -G gpio ubuntu

Reboot

sudo reboot

You should be able to run the script as following:

python3 stats.py

8. Run The Script On Start-up

Open up crontab by entering the following command:

crontab –e

Add the following line to the end of the file to run the script:

@reboot cd /home/ubuntu/OLED_Stats && python3 stats.py &

reboot and you should now have a working OLED stats display that starts up automatically each time your Pi boots up.

All credits to: https://www.the-diy-life.com/add-an-oled-stats-display-to-raspberry-pi-os-bullseye/

Worked like a charm! thanks

This works like a charm on Ubuntu Server 22.04.3 LTS as well. Please forgive my ignorance, but is there a way to convert to F or add F and cycle between the two temperature standards?