PixelsOut support for Waveshare 400x300, 4.2inch E-Ink display module

[ivandrosero]

Hello,

I am using the following ESP32-WROOM based device, integrated with a Waveshare's 4.2 inch e-ink display:

• https://docs.paperd.ink/docs/hardware/hardware/
• https://www.waveshare.com/4.2inch-e-paper-module.htm

I have working code using micropython, but I would love to switch to moddable SDK. Is PixelsOut API an option?

Pin-Out information below.

SPI Pins

• SCK: GPIO18
• MOSI: GPIO23
• MISO: GPIO19

E-paper Display Pins

• EPD CS: GPIO22
• EPD DC: GPIO15
• EPD BUSY: GPIO34
• EPD RESET: GPIO13
• EPD Enable: GPIO12

Thank you very much for your time and attention.

Ivan

[phoddie]

Welcome, Ivan, and thank you for the suggestion. I'm a big fan of ePaper displays and the Moddable SDK has extensive support for them (check out this blog post).

It is surely possible to to support the Waveshare display. It looks like a really nice display - big and a couple shades of gray in addition to black and white. In my experience, we end up writing a new display driver for each E-Ink display, because the drivers are often pretty different. The Arduino driver code for this display looks reasonably straightforward, but it is 600 lines of code to understand.

Do you have any experience writing video drivers? If so, I'd be happy to help guide you through bringing this one up.

[ivandrosero]

Hello,

I do not have experience writing one, but happy to give it a try translating to javascript. Looks like in this Arduino project

https://github.com/waveshareteam/e-Paper/blob/master/Arduino/epd4in2_V2/epd4in2_V2.ino

the place to look would be in the implementations of these headers:

#include "epd4in2_V2.h"
#include "imagedata.h"
#include "epdpaint.h"

?

Not a C/C++ programmer, but if you can tell me where to even put this stuff so that the Moddable build tools pick it up, and I can start debugging, that would already be more of a start than I currently understand.

Or, an it be done entirely in javascript?

Thanks for your tips here, much appreciated!