Waveshare 4.2inch E-Ink Display Module Compatible with Raspberry Pi 5/4B/3B/Zero/Zero W/Zero 2W/Pico/Pico W/Pico WH, 400x300 Resolution SPI Interface

Hooked it up to an ESP32 - works no problem! Yes, there was some reading and video watching I had to do to get the pins right (couldn't get it to work with ESP32-C6, but S2 worked perfectly! I probably had to spend a bit more time with the C6 - just was lazy). So, as far as display itself - crisp and works as expected from an E-Ink display.

Nothing unexpected, worked with my ESP32-WROOM-32D and platformio. When using the Eink library, use GxEPD2_420_GDEY042T81 as the eink driver. So the device initialization will look like this:// Pin Definitions for E-Ink Display#define EPD_CS 5#define EPD_DC 17#define EPD_RST 16#define EPD_BUSY 4GxEPD2_BW<GxEPD2_420_GDEY042T81, GxEPD2_420_GDEY042T81::HEIGHT> display(GxEPD2_420_GDEY042T81(EPD_CS, EPD_DC, EPD_RST, EPD_BUSY));

It works. Connecting the SPI interface with the supplied Dupont connectors requires care. One wrong pin and you could fry something. I triple checked everything. For people who can count above 2 this may not be a problem. Connected properly it works. Load up the Waveshare apis, use the right one and you're set.

My current project when I Changed from 1602 to e-paper last two or more days on a charge.

Agree with others, these are awful. Highly unreliable, with even the default code only works part of the time. You really need to find a good combination of hardware to work with these, and they all seem to have a short life. I've been using these for years and stupidly kept buying new ones to either replace the failing old ones, or trying to get the new ones to work. I regret going do this rabbit hole. A huge waste of time, due to the limited options out there.

These work great. I hooked them up to adrduino minis (3v) to create dynamic picture frames. Runs off of 2AA batteries. Picture frame updates every 3 minutes. So far both are still running on the original batteries (2 months).

Just clone the ePaper github repo and hook up as per below, module works great and looks even better:VCC => 3.3VGND => GNDDIN => MOSICLK => SCLKCS => CE0DC => 25RST => 17BUSY => 24

Documentation provided was good, product works as expected. Minor concerns are that the grays are 25% and 50%, instead of 33% and 66%, leading to an irregular color curve, but that's something that can be worked around, and mounting points not putting the actual display part in the center.