I have often wondered about the small ways in which we can re-use the electronics and waste less paper. I had an idea as of why not use less bulky electronic name tags which are easily rewritable and can be re-used by re-programming the display. So I decided to jump in last minute into this challenge by making one for myself which I can use in the future.
MAX7219 Dot Matrix Module For Arduino
Adruino Nando as it is small and portable
A small portable battery.
With some Arduino code
Four MAX7219 Dot Matrix Module
Connect them to the Arduino Nano using SPI bus DIN and SCLK. The LED matrix needs high voltage bias
Testing the first prototypes
Displaying Hello World and Welcome in the Dot Matrix
The final working Video
In my understanding re-usable electronics is the new way ahead.