For the most part, the build is what you would expect: a 16×8 LED Matrix display driven by a TLC5920 LED driver, with an Arduino that uses a DS1307 RTC (real-time clock) with a coin cell ...

So says [Vije Miller] in his write-up for his Arduino sand matrix printer ... resulting in something not unlike a dot matrix printer that can write messages in the sand. He’s submitted it ...