nRF52840-DK GPIOTE with FreeRTOS Tasks

RE: nRF52840-DK GPIOTE with FreeRTOS Tasks

Susheel Nuguru — Fri, 07 Feb 2020 08:12:15 GMT

An example on how to register for GPIOTE IN event with an event handler is shown in a very simple and clean way in nRF5_SDK_16.0.0_98a08e2/examples/peripheral/pin_change_int/main.c., this is exactly what you seek with GPIOTE as far as I understand.

Connecting the above example to tasks notifications and event handlers is a very straight forward task. Please attempt to do a template of your work and we can discuss here more on the challenges you are facing once you started to merge GPIOTE and FreeRTOS task notifications.

RE: nRF52840-DK GPIOTE with FreeRTOS Tasks

mpw — Thu, 06 Feb 2020 09:59:01 GMT

Thank you, Susheel.

I have spent a few days and I still don't feel I understand GPIOTE any better with the documentation available for the SDK 16.0.

It has notes on the documentation saying to use the legacy layer, but then proceeds to say to use GPIOTE registration and initialise the module with:

APP_GPIOTE_INIT(MAX_USERS);

What I am trying to achieve seems simple conceptually, but I wish to use the SDK correctly for future compatibility.

I want to register 1 pin for a transition from HIGH to LOW, then when that takes place I want a handler to be called and clear the interrupt (this is hard to find, too, is it handled automatically?), do some processing/raise a flag, then exit the handler.

The examples in the SDK don't make use of registration or anything of that sort and most of the handlers in the examples are using dummy handlers.

What is the correct way to use the GPIOTE module for simply initialisation, setting a config for high to low, passing a handler to GPIOTE module for callback, and then clearing that interrupt when inside the handler? It seems like a very powerful feature to have that I want to utilise properly.

Thanks,

Michael

RE: nRF52840-DK GPIOTE with FreeRTOS Tasks

Susheel Nuguru — Tue, 04 Feb 2020 08:41:22 GMT

Hi mpw,

What you are trying to achieve is quite simple using GPIOTE interrupts and FreeRTOS task notifications.

There are no direct examples of what you wanted to do, but configuring the GPIOTE to generate the interrupt with state changes on the pin you want and controlling which task to resume using the task notification is quite straightforward thing to do.