How it works:
The ATtiny wakes up the ESP32 every hour. The ESP32 accesses the Google Apps Scripts which provides a image URL from Reddit, it then downloads and decodes the JPG image and converts it into grayscale.
7" GT911 capacitive touchscreen
600x800 ED060SC7 Display (4bits of grayscale)
BQ24072 Li-ion battery charger for BL-5C
MCP9808T temperature sensor
Made possible by:
FPGA eink controller in which the ePaper driver chip (TPS65185) was identified to be suitable