Utilizing waveshare e-paper display on nRF52840 dongle with Zephyr RTOS

RE: Utilizing waveshare e-paper display on nRF52840 dongle with Zephyr RTOS

xiancong — Thu, 09 Sep 2021 14:57:27 GMT

Hi,

Sorry for the late reply, the links provided are very useful. Thanks a lot for your help!

Regards,
Xian Cong.

RE: Utilizing waveshare e-paper display on nRF52840 dongle with Zephyr RTOS

Øivind — Tue, 07 Sep 2021 10:36:59 GMT

This site has a lot of information about the zephyr devicetree, and how to write drivers for zephyr, the pages in the sidebar about devicetree and drivers would be relevant to read:

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.6.1/zephyr/guides/dts/howtos.html#write-device-drivers-using-devicetree-apis

There are many other posts about creating zephyr drivers if you search here on devzone or the internet.

I also found this, which is for the old nrf5 sdk, but might still be useful for some inspiration:

https://gitlab.com/hooeezit/waveshare-epaper-nrf52-dk-demo

RE: Utilizing waveshare e-paper display on nRF52840 dongle with Zephyr RTOS

xiancong — Mon, 06 Sep 2021 13:48:50 GMT

Hi,

Thanks for your reply. I have found the problem that causes it to not work.

The documentation from Zephyr about the display is actually referring to this driver while I'm using the 1.54-inch e-paper module. The driver comes with a micro SD slot while the module I'm using isn't, hence it's not working.

Currently, I have found the driver file for the module I'm using but it's for Arduino. I wanted to convert it to Zephyr compatible by changing some of the language references (e.g. digitalWrite, digitalRead...) but I'm not very familiar with Zephyr. May I know if there are any references that I can refer to convert the drivers to be Zephyr compatible? I believe I'll only need to change the .cpp files to make them compatible.

Thanks and regards,
Xian Cong.

RE: Utilizing waveshare e-paper display on nRF52840 dongle with Zephyr RTOS

Øivind — Mon, 06 Sep 2021 11:26:20 GMT

Hi, sorry for the late reply

By default, the available pins along the edges of the dongle seem to be:

P0.02
P0.09
P0.10
P0.13
P0.15
P0.29
P1.00
P1.10
P1.15

Try only using these pins, and see if that works.