Looking to use an e-paper display on a project , probably a largish 4.3”, I’ve not bought or used one before - bit concerned , do I need a lot of memory to map onto the display, is that likely to be an issue ? I’m hoping to display a graphic and just update a few text areas of the display, nothing too fancy .
Anyone out there used these and have any tips ? There is a confusion of prices , and memory usage is my main concern . Any thoughts ?
I’ve previously used the Nextion, the usual 16x2, 16x4 LCD and various others.
As a Senior Member of the Arduino Forum you certainly have enough experience to search in the Forum before posting a question. Searching for e-paper provides many results.
You explicitly ask about 4.3", without telling the reason.
Do you have specific need that would exclude the 4.2" b/w 300x400 SPI e-paper display, e.g. from Waveshare?
I know 3 versions of 4.3" b/w e-paper displays, I think they are 800x600, and have grey levels:
Waveshare 4.3" UART serial e-paper display,
LinkSprite 4.3" Arduino e-paper display for pcDuino,
Good Display 4.3" parallel e-paper display, usable with Good Display evaluation board.
All three seem to have the same display panel. Only the Waveshare one is easy to use, but power hungry. The panel shows more degradation of the displayed picture over time than other e-papers.
If you tell us more about your requirements, you may get more information.
Well that’s a good start . The 4.2” could well be a good choice. I did do some site specific searches , but posts were about specific coding issues and not about general use .
The project collects and displays data on a centralised display that needs to be readable from a distance , ( so I’m therefore concerned how much of a 328’s memory is needed )I also like the idea that it holds readings when powered off . It also looks more “ hi tech”
and readability outdoors would be good .The information I’ve googled suggests that there are two types - what I’d call a basic display and one with a processor and memory which is accessed serially . I’m guessing the more basic I2C versions require storage of the display within the 328 memory ? I’m not sure ?
I’m just interested in users comments - you mentioning them degrading over time for example is useful . I don’t see any particular problems in learning how to use as there are libraries etc out there .
I could just buy one and try it but , they are not cheap in that size. Someone out there might say “ model xyz is wonderful because .. “
The Waveshare 4.3" e-paper display has its own processor (STM32) with enough RAM for graphics buffer.
As far I remember you send graphics command primitives with parameters over serial to the display.
The Waveshare 4.2" e.g. (or the panel from Good Display) has its controller with RAM for display refresh, but no graphics commands, and the RAM is only addressable on byte level. So you need a graphics buffer in the display driver class for general graphics or text rendering (300*400/8 bytes). For AVR Arduino, e.g. Atmel 328 you need a display library that supports paged display, e.g. GxEPD or GxEPD2.
