Introduction: Digital RPi LED Thermometer
Raspbian OSLearn how i made this Digital LED Thermometer, with a Raspberry Pi Zero W, LED strip, an OLED Display, and a custom PCB.
It automatically cycles thought a list of cities, and displays the temperature on the OLED display, and the LED's. But you can also manually select a city to display, with the buttons on the side. On top of that, it will shut off the LED's and the OLED, if it's been inactive for a few minutes, and will turn back on, if it detects a significant light change (Controlled by an LDR).
- Screws, washers, bolts and standoffs.
- A Custom PCB, with buttons, a switch, an ldr, pin-headers, and more
- Soldering iron and solder
- Hot glue
- Wood glue
- 4mm and 6mm plywood
- 3mm white acrylic
Step 1: Weather Data
Credit to StuffWithKirby for his code on reading JSON weather data in python.
I collect the weather data free from OpenWeatherMap.org, where they supply weather data from a lot of the bigger cities, in a lot of countries.
1. Start by making a FREE account on OpenWeatherMap.org.
2. Then copy your api-key to use later.
3. Now download, unzip and open the city.list.json.gz file, and search for the cities you want displayed, and copy the city-id's for later.
Step 2: Setting Up the RPi and Writing the Code
First I connected the OLED to the Pi, and installed the necessary libraries for the OLED, as described by the manufacturer, here.
Make sure the RPi is connected to the internet
1. Enable the I2C and SPI function in raspi-config under Interfacing Options. Exit and reboot.
2. Run this to update:
sudo apt-get update
3. Run the following commands to install the necessary libraries:
sudo apt-get install python-dev sudo apt-get install python-smbus sudo apt-get install python-serial sudo apt-get install python-imaging
4. Run the following command to open the configuration file:
sudo nano /etc/modules
Make sure the following two lines, are in the configuration file, then exit and reboot:
5. Now run this to clone my GitHub repo:
git clone https:/ /github.com/Anders644PI/1.5inch-OLED-with-RPi .git
6. Go into the new folder, and unzip RPi_GPIO-0_6_5.zip:
Run this to install the library:
cd RPi_GPIO-0_6_5 sudo python setup.py install
7. Go back to the main folder, by typing by typing:
Then do the some with spidev-3_2.zip.
8. Then unzip wiringPi.zip:
unzip wiringPi cd wiringPi
And run these commands:
chmod 777 build ./build
Check the installation with:
9. Go back to the main folder, and unzip bcm2835-1_45.zip
unzip bcm2835-1_45.zip cd bcm2835-1_45
10. Then run this, to install the library:
./configure make sudo make check sudo make install
11. Again go back to /home/pi/1.5inch-OLED-with-RPi/, and run this, to test the OLED:
cd /Demo_Code/Python/ sudo python main.py
Then i also had to install the libraries for the WS2812B LED-strip, following this guide.
After that it was just a matter of writing the code, which took about a couple of months from start to finish, working on it on and off. My code can be found on my GitHub here.
Step 3: Configuring the Weather API
1. Cd into LED_Thermometer_Code_and_OLED_driver:
2. Then open Official_Digital_LED_Thermometer_v1-0.py:
And then scroll down and edit the api-key, to your api key, from openweathermap.org, as shown in the image above. Also change the city-ids and city names, to your desired locations.
Step 4: The Custom PCB
After having figured out all of the electronics, I designed my own PCB, to have everything connected neatly together, and got it fabricated and shipped from China.
Step 5: The Laser Cut Enclosure
Then I modeled an enclosure, and laser cut it out of 4mm and 6mm plywood. I also modeled in LED diffusers, which I cut out of 3mm white acrylic.
After that I attached the electronics and the LED-strip to the laser cut plywood. And then assembled the enclosure, partly with glue and friction, so I can take it apart if i want to.
As an added detail, i also 3D-printed button and switch extensions, so they are easier to press.
All the files, can be found and downloaded from my GitHub. You may have to scale the SVG files down to 75%.
Step 6: The Result
Second Prize in the
Raspberry Pi Contest 2020