This is repository for an art-technology project called "20x20". The project is in one way a tribute to the era of limited resources, when each pixel mattered a lot and could change the visual content. On the other hand the project is an exploration of using a minimalist way to convey information in public spaces.

The basis of the project is an array of LED diodes arranged in a 20x20 matrix. The display is located in the lobby of the Faculty of Computer and Information Science at University of Ljubljana. The display is controlled by a Wemos D1 micro controller running a custom firmware based on the NodeMCU project.

Contributions are welcome, you can provide new visualizations (tiles) or enhance the supporting system. Use pull requests to do so.

Repository consists of several parts

• Lua code that is run on a Wemos D1 micro controller which controls an addressable LED strip of 400 diodes. This are the core and tiles folders.
• The firmware folder contains code for building a suitable firmware image. The code requires custom native modules as well as a predefined set of standard modules. See the section below for more information.
• Python tools that are run on a computer and provide a simple emulator, a converter of images to sprites and a tool that uploads files to the micro controller. Install requirements from the requirements.txt file to use them.
• Some graphics resources.

Since the code requires custom native modules, the firmware can be built locally using the nodemcu-build Docker image. Use the build_firmware.sh script found in the firmware folder to build the firmware.