eInk Display not included Shares the SPI port the eInk display uses, so you only need one extra pin Control up to a 4.2' 300x400 tri-color display (300*400 * 2 colors / 8 bits-per-byte = 30KB) Add all the power supply support circuitry and level shifting so you can attach your favorite display Use the SRAM to set up whatever you want to display, then shuffle data from SRAM to eInk when you're ready