Hi !
Due to huuuuge eyestrain issues I’ve been kinda abandoning most of my projects depending on screens (which are : most).
Would it be possible / reasonably usable to build a zynthian with an e-ink screen ?? What do you think ? Apart from the obvious caveat of the lack of usability in a dark environment !
Cheers everyone
My 2 cents. Those kind of displays are not meant for displaying data that’s constantly required to change very often. A full refresh of the display can take seconds and while partial refreshes are much faster, they can cause ghosting damage unless a full refresh is forced regularly.
So, best avoided in my opinion.
Regards
James.
Yea, Eink update is sluggish, the rotation indication might be a blur as you rotate a control.
I got a 2 color Eink display, (“3 colors” counting B, R & W) which takes some 15 seconds to repaint the screen, some bigger ones, can draw just the changing area in less time.
The drawing ‘flicker’ is shown at 5:32 of this demo video.
OLED’s might be another way to get more vivid colors.
Waveshare.com sells a variety of display type (including eink) a newer technology they have
is the 5.5inch Capacitive Touch AMOLED, with Tilted Case, 1080×1920, HDMI $134.99
This is the technology the highest qualoty big screen TVs use.
https://www.waveshare.com/5.5inch-hdmi-amoled-with-case-b.htm
This article mentions the possibility of constant paterns (like old bank ATMs used to get. Shifting around the position of fixed menus a bit can reduce the burn in effect.
Another higher fidelty screen that might do well
(looks like it can display ModUI screens)
The hyperpixed screens are gorgeous. I’m actually waiting for the non-square shaped touch version to come back into stock so I can build another zynthian.
Have my 3D printed case ready. Got the design from Thingyverse and I modified it to my needs. For example, I don’t want the SD card exposed. Might print this again though after I do a service on my printer. The head seems to be a tiny bit loose so it’s not as clean of a print as it could be. Love this PLA though, it’s very shiny.
Regards
James
PS… my main reason for using the Hyperpixel is that I find the resistive touch screen’s very inaccurate, where a capacitive one would be a dream to use in comparison.
OK guys, thanks for your reply.
There are some pretty responsive Dasung screens but they are very expensive…
(around 15 frames per second)
It sounds like the issue is contrast and size… Any possibility of plugging in a full sized HDMI monitor? I’ve built up a number of “headless zynths” around an “Argon One” case and “Sabrent USB stereo sound adapter”. I connect this to a full sized HDMI monitor when needed… To the right hand side is the 4 encoder/ 4 button Arduino USB HID Controller which I use to control the zynth.
I’ve just found this. It offers a big eInk display + ESP32 + LiPo battery + wifi&bluetooth + I2C UART ports + USC-C connection for charging the battery and loading the firmware.
below are the given refresh rates:
maybe too slow, but nice product otherwise.
A different option, but I have not researched how good it might be
Nice. That’s a fast e-ink display for sure, and overall a very nice package. So many cool toys to play with.
The Touch version of the Hyperpixel’s are back in stock so I’ve ordered one of those this morning. The hope is that the capacitive touch screen is easier to operate than the resistive. I find the resistive triggers false selections and you have to be very deliberate in your selections.
James
Just for reference 30Hz refresh is 33ms. These update rates are slow, and the M5Stack video shows some examples where you can watch the screen get painted line by line. That’s not a stylistic animation, that is the performance of the display.
Still probably fast enough for a zynth display, and I’d love to see one 
