It's a Wordclock! See a full walkthrough of the build on my website: https://www.jeremyblum.com/2016/02/03/wordclock/
- Prep a Raspberry Pi.
- These instructions have been tested on a Raspberry Pi 2 B running The "Buster" Raspbian Lite OS Build (Kernel version 5.4.72+), but newer Pi hardware should work too.
- Create an SD card with the Raspbian Lite OS Image (no Desktop GUI is needed for this)
- To enable headless setup, add a file called
ssh
to the boot partition root directoy (no extension). This will enable SSH on boot by default. - If you are using a Wi-Fi USB dongle instead of Ethernet, plug it in, and configure the wpa_supplicant.conf file in the boot partition so that the pi automatically connects on boot.
- Solder the shield (https://www.adafruit.com/product/2345) together, and add a jumper wire between pins 4 and 18 so that the RGB library can be run in the highest quality mode. This is described in the Adafruit documentation linked below.
- Connect the shield to the Pi, and install the coincell battery for the RTC
- Connect the Pi to Ethernet, or install a supported Wi-Fi dongle into one of the USB ports if you haven't already.
- Connect a 5V, 4A power brick to the shield.
- Power on the Pi, and connect via SSH using the default password. (Check your router for the DHCP-assigned IP address)
- Setup the time zone and change the default password by running
sudo raspi-config
. I also suggest expanding the SD card partition and reducing GPU memory to the minimum since the Pi is running headless. - Install all the latest updates using
sudo apt update && sudo apt dist-upgrade -y
. Reboot when complete. - SSH back in and run this command to download and run an installer script (forked from Adafruit to use a newer library version):
curl https://raw.githubusercontent.com/sciguy14/Raspberry-Pi-Installer-Scripts/master/rgb-matrix.sh > rgb-matrix.sh && sudo bash rgb-matrix.sh
. This will install the RGB panel libraries and help configure the RTC. Run the script from the home directory (/home/pi). Choose the "QUALITY" option when prompted if you've added the solder jumper described earlier. Reboot when complete. - Install pip for python3 and numpy:
sudo apt install -y python3-pip libatlas3-base libgfortran5 && sudo pip3 install numpy
- Set the RTC Time
- Run
date
to confirm that the date/time that was retreived from the network time server is correct. If not, check your timezone settings. - Run
sudo hwclock -w
to write the current datetime to the RTC. - Read it back with
sudo hwclock -r
and confirm it is correct.
- Run
- SSH back into the Pi and clone this repo to your home directory (
git clone https://github.com/sciguy14/WordClock.git
). You should now have aWordClock
folder and arpi-rgb-led-matrix
folder in your /home/pi directory. You can delete thergb-matrix.sh
that was used to install the libraries. - Confirm that everything is functional by running one of the library demos:
sudo /home/pi/rpi-rgb-led-matrix/examples-api-use/demo -t 10 -D 4
- Navigate into the
WordClock/Software/
directory and makeWordClock.py
executable:chmod +x WordClock.py
- Install screen:
sudo apt install screen
- Add this to crontab (
crontab -e
):@reboot screen -dmS wordclock sudo /home/pi/WordClock/Software/WordClock.py
. By launching the script in a screen, you can easily ssh in and attach to the already running session to see debug output without having to kill and manuall relaunch it. - Reboot.
- The wordclock should run and show the time after reboot. It is no longer necessary to keep the wordclock connected to Wi-Fi/Ethernet, as the onboard RTC will keep time. But you can keep it connected if you want to ensure that you stay syncronized with the network time server.
This work is licensed under the GNU GPL v3. Please share improvements or remixes with the community, and attribute me (Jeremy Blum, http://www.jeremyblum.com) when reusing portions of my code.