Hi There, great project. Love you SoftSPS approach :-)

Makes it a lot clearer for me what is actually happening on the bus.

Where did you find all the insides for PanelSettings? 

I'm busy struggling with some ePaper Displays from "GoodDisplay" like this one http://www.good-display.com/products_detail/productId=368.html

I'm a bit afraid to break it if I temper with the data. There are a lot of documents along with the display but this doesn't really help me (too much information). Maybe there is a simpler way if you could explain where you found the indexes.

Tried your code with this breakout board: http://www.good-display.com/products_detail/productId=362.html and a 4.2" r/b/w Display.

 http://www.good-display.com/products_detail/productId=322.html

400x300 display, so 0x0190 times 0x012c so much I could figure, but unfortunately the display does nothing at all :-( how would you debug this?

After some hours of testing, I found GxEPD-Library and figured that I missed to put BS-pin to Ground:

DESTM32-S2 pinout (top, component side view):
         |-------------------------------------------------
         |  VCC  |o o| VCC 5V  not needed
         |  GND  |o o| GND
         |  3.3  |o o| 3.3 
         |  nc   |o o| nc
         |  nc   |o o| nc
         |  nc   |o o| nc
         |  DIN  |o o| CLK 
         |  CS   |o o| DC   
         |  RST  |o o| BUSY  
         |  nc   |o o| BS  ->  GND
         |-------------------------------------------------

some problems just solve themselves :-)

Is there a Teensy wired up to the breakout board?

I'm wondering if this would work with the FancyEPD library  https://github.com/zkarcher/FancyEPD

I modified your breakout board, all capacitors are now 0805 (they are cheaper and might be easier to solder for others) and all traces are 10 mil minimum. Routing is changed, too, but it still fits on the same board size. OSH Park is really nice, easy to order:

https://oshpark.com/shared_projects/n9KwWEY1

I added the Open Source Hardware logo, I hope you don't mind. I can add your webpage and logo again, too, was not much room left on the top silk screen anymore, but maybe it will fit in the center. For my final board I will draw this again in KiCAD anyway, including the solar cell, super cap and ESP32 module.

This is the Digikey cart to populate 2 boards, and including one display:

http://www.digikey.de/short/3n91f9

For the cheap parts I rounded up to the next price break. Are all parts the right ones? I used another inductor than you used.

Looks good! If you want to add my url on there that'd be cool, but I'm not gonna force you or anything :)

The inductor looks to be identical to the one I used? IFSC1515AHER100M01

Let me know how it works!

Right, looks like it is the same inductor, I was confused by the SparkFun library. But will need some time until I can test it, because I chose the free shipping from OSH Park.

PS: my hand-routing, with optimized parts placing, needs only 15 vias compared to your 17 vias :-)

Looks really good!

Very exciting!

Screen in question: E2417CS051  available for $48.5 (as of 4-17-2017)  in single qty on digikey  http://www.pervasivedisplays.com/products/420

Note, I asked Pervasive Display with the support page, just to be sure, and this is what they answered:

"DigiKey has not yet placed the 4.2” with red on their website. Please contact MSC ( https://www.msc-technologies.eu/products/displays/passive-displays.html ) they have them in stock"

Another guy from Pervasive Display contacted me, now it is available from Digikey:

http://www.digikey.com/product-detail/en/pervasive-displays/E2417ES053/E2417ES053-ND/6211106