RE: NCS v2.6.0: Instructions to use GPIOTE and Zephyr GPIO API

Nathan45 — Thu, 11 Apr 2024 19:42:40 GMT

Just wanted to add a few details that I left out:

Device Tree Overlay Fragment

You should add the following fragment to you device tree. This is because there are TWO different GPIO interrupt mechanisms (at least on the nRF52840!). One is through the PORT event and one is through the IN event. The IN event is what we need and actually requires a different hardware "path". But don't worry! it's not difficult! Just add the below to your overlay and change the following to your needs:

gpio0: gpio@50000000

gpio1: gpio@50000300

(find the gpio bank in your device tree and use that)

and also change the sense-edge-mask value to select the correct pins! I think you need to mask the bit position of the pin as 0.

soc 
    {
        gpio0: gpio@50000000 {                                          
            sense-edge-mask = < 0xffff3fff >; Use a bit mask for the needed pins!!                       
        };
    };

As an aside, I'm not sure if the project I linked to that I made includes this (I deleted my device tree except for the minimum right before commiting).

Prj.conf

https://github.com/nrfconnect/sdk-zephyr/commit/a86ac1f8c2a48e32ed824f0f5ea49d45ceaa345f

It seems to indicate that the config

CONFIG_GPIO_NRFX=y

is necessary, but I'm not sure. You may want to try this in lieu of or in addition to

CONFIG_GPIO=y

RE: NCS v2.6.0: Instructions to use GPIOTE and Zephyr GPIO API

Sigurd Hellesvik — Thu, 11 Apr 2024 07:55:21 GMT

Hi Nathan,

Truly impressive!
Thanks a ton for the excellent explanation of both the problem and the solution!

In technical support, we use a list of "frequently asked samples" as a lookup table to help our users faster, and this post goes straight into that list.

Again thanks,
Sigurd Hellesvik