DIY Hourglass for Arduino, based on MAX72xx, Arduino Uno, LED matrix... Code : http://www.github.com/asthro/sandclock Model : http://www.thingiverse.com/thing:1316240 Information : http://www.asthrolab.fr/?p=1242 http://www.blenderlab.fr/2016/02/03/sandclock-for-arduino-un-sablier-pour-arduino/