Simple wall calendar

The e-ink displays from waveshare store are looking attractive and are very interesting. This project is a try to manage a high-resolution display yet, it was a chance to create own variant of HAT board and investigate the FPC type connector.

This project is about how to build very simple wall calendar. The main component of the project is a 3-color (Red-Black-White) 7.5" E-ink display from Waveshare. The month calendar refreshes once per day, at midnight. To make the calendar more interesting, the moon phase and sunrise and sunset times were added to the calendar.

To manage the calendar there are several push buttons on the bottom side of the PCB:

• wkup - to activate the calandar MCU from sleep mode.
• menu - to select the time or date item to be modifed during the calendar setup.
• plus - to increment selected item during the calendar setup.

The very firtst release supports only two languages: enhlish and russian. Yet, the geographical coordinates that are required to calculate sun times, are hard-coded into the source code. Perhaps, you have to recompile the project and load your custom firmware into the calendar.

The calendar powered by li-ion battary and has a built-in charging controller to recharge the battery. Average battery life of 3000 mAh battery is about 6 months.

Here are pictures of the project schematics also available os a EasyEDA project here. The source code is published on the github.