Clock Build is a hacker master, and overflows with many energy-thirsty LEDs and network features. From this construction [mattwach] For e-paper based design it takes the exact opposite approach with a sip on the battery.
The build relies on a small waveshare e-paper module that only requires power when the display changes. When stationary, the display does not require any electricity and it helps to save a lot of energy compared to OLED or LCD-based watches.
An Atmega328p has a 32.768 KHz clock crystal closure for a combination of build focal point, precise timekeeping and low power draw. Time is guaranteed to be both precise And Exact thanks to a GPS module that allows the clock to sync with satellite time when powering up. This is a common way to sync the clock to a high-quality time source. Most of the time, though, the GPS is driven to save the 30-100 mA that you typically draw when using the module.
Other features include a temperature, humidity and pressure sensor, whose ambient pressure is graphed over time. The current phase of the moon is accompanied by notifications of sunrise and sunset times. It is flavored using 3D printed parts and some wood CNC-cut panels for a beautiful rustic look.
If the microcontroller is configured for e-paper display and low-power operation, the clock will run for about 6 months in four AAA cells. Overall, this is a nifty mini clock that will provide time, date and other information without the need for internet connection. Video after the break.