Haiku Display Console

My next project started out as a standalone unit (ie. battery powered) for displaying haikus.  These are poetic forms of Japanese origin that consist of three lines that follow a five-seven-five format (five syllables in the first line, seven in the second and five in the third).  Since I wanted it to be battery driven, I chose an e-Paper display. These displays are ultra-thin, low power units that will hold an image or text for long periods of time without power.  Perfect for my needs. I chose an ESP32 board for my controller because of its Wi-Fi capability and its large memory capacity for holding potentially dozens of haikus.

Initially I planned to incorporate the sleep functionality of the ESP32 to minimize battery drain.  The controller would select a haiku at random and display it, go to sleep for two hours, wake up, display another haiku, go to sleep again,  and so on.  Also, since this type of display needs ambient light to work, it didn't make much sense to keep it running 24hrs a day since the room it was going to be placed in would be dark in the evenings.  Therefore, I planned to put the unit to sleep during the evening and early morning hours (again, to save the battery). 

After writing the code and using a public domain library to interface with the display, I ran some tests to see how long it would work on a fully charged battery.  After about four months it finally stopped running.  I didn't count on the fact that periodically checking the time online would drain the battery so quickly.  Ultimately, I made the decision to scrap the battery idea and use a wall mounted unit for my power source.  This had the added benefit of eliminating the hassle involved in having to keep recharging the battery 3-4 times a year.

To complete the project, I made a custom enclosure out of maple and wormy chestnut to hold the display upright while keeping the electronics hidden underneath.  A few weeks after finishing up, my wife and I both got inspired to write a few of our own haikus while hiking around the Blue Ridge Parkway.  I uploaded these into the controller chip and we now look forward to seeing one of our poems randomly "popup" on the screen from time to time.

A "traditional" Japanese haiku

A haiku written by my wife

Side view showing display thickness