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Digital Hourglass

To be honest: If you’re not working, you don’t really need an exact time: it’s about afternoon, I’m hungry, I’m tired, it’s time to go to bed. And in the morning, the alarm clock on my mobile phone wakes me up again.
In the meantime, an hourglass would be enough to show the passage of time. Unfortunately, the large hour glasses are hardly available any more.. Only small ones for the kitchen that show maybe 3 or 5 minutes.
That’s why I built an hourglass that takes exactly one hour to run through. The hour time is still displayed as a number in the top glass.
The construction and programming are simple, and there are no limits to the imagination when it comes to the outer design.
Have fun rebuilding it.

Basic knowledge of Arduino required.


- ESP32. (e.g. Arduino nano is too slow)
- 2x. GC9a01 round display
- RTC module
- wires
and material for a housing: wood, cardboard, plastic, 3D print, …”

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