Hi Ralph. Great work as always! I’ve worked extensively with the 1.54” displays for the last 9 months developing a product prototype. I’ve got both MH-ET Live and Waveshare brand displays which both use the GoodDisplay displays. Both very nice with the WaveShare being a few mm smaller in physical size. Other than that, they’re both great. Neither have the extra sram memory. That’s why I use mine with ESP32s. Yes, the colour displays are a real disappointment when it comes to refresh times. In fact, the 1.54” black/white/yellow version doesn’t even have the same resolution for it’s size when compared with identically sized b/w and b/w/r displays. And for that reason, you can’t use the same library. What a pain. But the black/white displays are glorious. My app has bitmapped images changing on the screen maybe every 15 seconds and after 9+ months of heavy use, there’s no damage to the b/w displays that I can detect. I’m running mine off esp32 Dev boards like my air conditioner project I showed you back in the summer. No issues. I will say that the partial update mode on the b/w displays is critical to the usability of epaper. The colour ones don’t support partial update so that’s why the full screen updates are the only option. I will say that it seems for mine that rotate really only applies to text and maybe graphics primitives. The bitmap images can’t be rotated in my experience. So I just rotate my images 90 degrees clockwise before I render them as bitmap byte arrays. No problem. I’m a fan of the b/w displays. I won’t be buying any more coloured ones. We’re now starting to see some displays that handle 3 or 4 shades of gray/red. But I expect that’ll still have a refresh performance hit. Enjoy your epaper!

Calendar, TODO list, high speed gaming display for Treebeard the Ent.

The strange update restrictions are not intrinsic to ePaper technology, I suspect these devices have been heavily optimised for low power and display retention at the expense of other qualities, and I suspect they are really intended for labelling applications. After all, the original kindle display was ePaper and has a very fast update, and can be updated as much as you like. Perhaps one of these might make a nice pocket appointment reminder updated every 30 mins or so? Perhaps with a docking station to charge it and provide connection to update the appointment list. As usual Ralph a very interesting video - keep it up!

Ralph sure like that the sound level is so consistent between the cuts thanks. I had my 5 year old grandson last night he had a restless night and we watched you twice Glad to see you back at it 😀

I have a temp/humidity sensor which updates every 4hrs so this would work for me. Didn't know anything about these so this was super useful cos I put the ESP32 to sleep after sending data to Google Sheet so it could still show latest value. Very useful video for me! Thanks

Thanks Ralph, back when I was fooling around with that stuff I tried using an Epaper Display to no avail. I wanted to make a simple outdoor weather station that would gather data points every do often, but it would only transmit the data back to the indoor reviver station with the Epaper Display. I figured gather data points every minute or so, and then transmit data every half hour or if there is a sudden sustained change for 7 minutes or longer. Indoors you can track of your outdoor air pressure to see if it's rising or falling. The EpaperDisplay would be perfect to show the temp., humidity, rising or falling pressure, if it has been raining or not, and total rainfall today, e.t.c.

Thanks Ralph. This is a technology update for me. I played with a B/W e-paper display a while back and found it to be an interesting device but not one for which I had an immediate need. A couple of interesting points: my devise had no warning about continually applying power or about frequently updating the disply, and (if memory serves) I had the ability to update a portion of the the screen. I clearly remember watching a display with unchanging text and a counter that updated on the second. The update time for the counter was only a fraction of the time required to update the entire screen. This was a strong point for me, so I hope they have not lost this feature.

Great investigation into an often overlooked type of display. Thanks!!

One use I put these too a few months back was a weather centre running on esp32. It displayed data from opennweather website through their api. This gave hourly and 5 day forecast.. Added humidity, temp, pressure sensors as well. Worked great on batteries with these displays. A crappy lion cell gave 2 weeks and if you upped the capacity you could have had months. Update was every 20 mins I think.

I have been using a 4.2 inch screan displaying a weather station by UKposts presenter G6EJD - David . It updates every 30 mins with just a small flash but it is only black and white and then the ESP32 goes to sleep. It might be worth getting in contact with Dave as he has done a lot with this type of screan.

Very informative video SIR

Have had a Kobo Glo ereader for several years now... love it or the epaper display - WITH BACKLIGHT!!! Naturally Amazon then copied the idea! ;) It can do partial refreshes a lot faster, and a full refresh in under 2 seconds. I played with a black/white epaper display with an ESP8266 (I avoided the tri-state ones because of the time issue), and was updating it every minute like a clock without any issues. I also have a eink temperature/humidy display that updates every 30 seconds or faster, but that is only partial refreshes, and then a full screen refresh every half hour or so. It is pretty neat tech, and is perfect for things you want to be able to update, but not fast... things like price tags (as you mentioned), calendars, temperature, id tags, etc.

I've been using a Waveshare 4.2 BWR display for a year now driven by a LOLIN32 using the GxEPD2 library and I do a refresh every 30 minutes, it displays the next 11 events in my Google calendar because my memory is rubbish.

Good day, again, Ralph. I don't know if I could have some use for such a display, but it sure is good to know it's something that exist. One thing pops to mind, though. Is it possible to have some shades of grey or it's only black and white .. and red ? The absence of mid roll ads is something I appreciated watching this video. Thank you, my Friend ! Have a great day and stay safe !

Hey Ralph, got my first ePapier Display about 4 weeks ago. And went a totally different way than you did: we're using the display for displaying measurement data over a rf24l01 connection. The display is a 4.2/300x400 pixel waveshare display with some logic onboard (and no color), so I can interface an ESP8266 (WEMOS D1) to the display without a lot of hassle - and without tearing these flex-connectors :) The ESp seems to be a way better match, since I didn't struggle with SRAM. As a library, I went for the GxEPD2, and after the intial cursing and hair-pulling, this really starts to work great. There's much similarity to the u8g2 for OLed Displays, so it feels a bit like home. GxPD2 can use the Adafruit GFX Library, so you get graphic primitives the easy way. And - you can import your own fonts. Adafruit has a fontconverter for that - wich you have to compile yourself... I know: what? So I threw it all into a VM, installed all these tools I'll never used in my life and did a successful compile run... talking about wasted time... anyways: it works. Refresh times for BW aren't that bad - I measured about 700ms for a complete screen refresh - while your MCU does nothing else. That could be bad for anything time critical (i.e. Wifi), but that's what you get. We do partial refreshes every two seconds - up til now the display didn't fail. Not sure if the 180 seconds you mentioned are only for colour displays - we're going to try this out :) Partial refreshes work pretty good - even after hours of 2 sec updates, text won't degrade. So - maybe your countdown can be done some way?

I would try drawing the red rectangle, then the white-text-with-red-background on top.

Interesting. I'd been thinking about getting one of these to use in place of an OLED on some of the test fixtures I build. I guess that wouldn't work out very well, so thanks for the video. I wonder how this is different from what they use in things like the Nook Glow? Because I can flick back and forth and have it refresh the screen once a second or so, and it doesn't seem to have any problem. Also, none of the weird flashing and flickering during updating.

And I do recommend the GXEPD2 library from Marc Zinng (ZinngM) on github. Really well supported.

Well that was disapointing. NOT your video, but thr EPaper display. It is truly challenging to percieve a UI that would benefit from such a static display. It could be used to indicate the time of the next step in a sequencer such as a central heating control. It could be used to indicate the detail of the last alarm. However, it would be useless for programming a central heating control and the alarm indication would only be useful until one tried to change settings etc in response to said alarm. Oh! I just thought of an application: it could be used to display the contents of a large text file, given that it takes a few minutes to read the page. Somebody should take that idea up. I really had high hopes for EPaper. The fact that it draws no power for displaying static text would be very useful but the reality kinda puts the khyber on an interactive UI. Thanks for the very valuable heads up and for taking one for the team.

If you decide not to clear the page but rather ad a second line of text under the previous printed text line, can that be done without the 3 minute delay?

I've not tried the 3 colour version, been using a b&w epaper display from waveshare for 3 years in my radio streamer project to display the radio station logo, the unit failed a couple of months back, I had a spare available that I swapped out, from checking the failed unit the epaper part is ok, it's the board that has failed, the board on the replacement is a slightly different design in that it has a chip that my original doesn't have. Reason I went of an epaper is that I use my radio streamer in the bedroom and didn't want a display that would be noticeable when wanting to get to sleep, with it's high contract I can easily see the logo from 4 metres away. For the first year I was doing partial refreshes, you can get 3 to 5 partial updates before the logo shows fade from previous refreshes and you'd need to do a full refresh to get it vivid again. I now just do full refreshes, the appear of partial refreshes isn't as important as I thought it would be. Next I'll be looking at what to show on the display when I'm not playing the radio, thoughts are ISS passes, local weather, tide and river levels. github.com/lakeuk/Runeaudio-extensions

adafruit's gfx library (lacks basic functions for many boards), MQTT library (doesn't have several standard things like retain bits etc), and others have a lot of issues and are poorly written. It's unfortunate because they charge a premium for their devices.

I always thought these displays would be good for a event days count down. Only update the display once a day (Midnight). Like 125 days til Holiday, or wife's birthday, anniversary

Hi Ralph, nice looking displays but can't think of a use for myself at the moment and a bit pricey.

I have the ttgo esp32 epaper display with the badge demo code. still showing the same information i wrote to the screen over 3 weeks ago and haven't given it any power since writing.

I played with a three colour epaper display and only got it runnig with a lowlevel library. It uses two bitplanes, one for black and one for red. If I remember correctly on both bitplanes, white is represented by 1. So I guess the library you used did not produce correct bitplanes ?

The reason for the flick when using red, is that the RED ball in the bottom of the silo, that holds the colour balls. Interesting walkthrough👍😀

hi Ralph can you do a video on SPIFFS , i wanted to run a full website using SPIFFS and call elements from the normal memory but just cant get my head around it . your style of education is at my level of understanding . so i ay have a chance of following it.

The maximum 3 minute update rate is a real kick in the teeth :( Does the basic monochrome display exhibit the same restriction?

Got a bunch of e-paper pricetags and they are a perfect usecase for them see an example of hacking them here ukposts.info/have/v-deo/m2ZjeGmRZJlmqoE.html With a custom firmware on the internal chip the estimated battery life is at about 5 years with 3 updates a day

I often order things and then think why, like oleds I get confused see a nice picture and then the thing arrives tiny about the size of a postage stamp and I cry a little for not fully reading the blurb:-)

Hey Ralph! Depending on the display, so long as you flash full black, full white on refreshing the content, you can update it semi-frequently. If you look at the Amazon Kindle or any similar e-reader that uses eInk, they have ways to get around the limitations of the refresh rate. You wouldn't be able to put a countdown clock on it, but you might be able to use it for a clock or something every minute (since you could just refresh those pixels), depends on the technology though. I got a 2.75" screen to test things out with, but it needs a bit of a better processor to be able to handle the buffering and management of refreshing the individual sections. Edit: I also think u8glib2 has support for epaper displays too, which is quite a nice display library. :)

Hi Ralph interesting display, your talk about powering off the display after an amount of time. A thought came to me could you not combine your project on the MOSFET power circuit to power off the Display when not in use and only power up when the Arduino has something new to display and it’s over 3 minutes.

Not uncommon for Adafruit code to have a lot of bugs in it. Or library code in general for that matter. Many of them aim for quantity instead of quality.

32k bits is 4k bytes, btw. :)

Nice video Ralph! They are frustrating little beasts aren’t they? I have been playing with e-ink display for my GPS project, using an early 1.54” 200x200 pixel screen from Heltec, and found the GxEPD2 library from Jean-Marc Zingg very helpful. Provided you remain aware of the potential to harm the screen, his partial update routines are brilliant. My display shows a square labelled for the OS Map grid reference (calculated from the GPS lat/long) and moves a dot around the square in real time using partial updates, representing the user’s location. Full refresh when you move to a new square. I have a version that runs on the same 2.13” Adafruit RBW screen, but without the partial updates. I think the Adafruit extras might mean that you’re locked in to using their library. Do take a look at Zingg’s excellent work here github.com/ZinggJM/GxEPD2

IMO using these for pricing, says "dishonest business practice is standard here." Like, "this was $5.99 for the last guy, (the one in the cheap tacky track suit), but for you... in those threads... looks like you'd pay $9.99 (as the prices roll on the next isle over).' - So basically scAmazon. I haven't used epaper before. I thought about putting one in an AVR transistor tester at one point, but never did. It would be nice to have the transistor pinout remain visible until the next test is done. I thought it would be cool to use one of the tiny displays for a battery indicator on a deep sleep battery powered project. For a larger type of display like yours, I think I would make a daily weather forecast display although something like that is better suited for an ESP8266 or 32. I don't think it will help, but Ben did a video on the refresh physics behind epaper on his Applied Science channel awhile back :-) ukposts.info/have/v-deo/haOTnYVvfHekqKs.html Thanks for the upload. -Jake

I think is really cool technology but the implementation reduces the use cases

Hehehe new haircut, DIY i suppose? :)

Hi Ralph, here’s a link to Kevin Darrah’s work with ePaper displays and low power MCUs. www.kevindarrah.com/wiki/index.php?title=EPaperBoard . His video encouraged me to buy a 4.2” screen and experiment. I used mine for a while display the data from my weather station. Unfortunately the weather station stopped working but I’ve not been successful in troubleshooting it.

Price aside, I'm disappointed in the technical limitations of these displays. The aesthetics during refresh are horrible, and one refresh every 180 seconds - can you imagine how few Paperwhites Amazon would have sold were the experience similar? Yes, I'm sure there are use cases for this display, but they seem to be few and far between. After all, if an imaginative guy like you struggles to find a use...

"Sorry, did you mean Office Fan?"....

Lets face it, its expensive, its very very very slow, basically, it complete RUBBISH !