nRF52840 GPIO definition issue

RE: nRF52840 GPIO definition issue

adragocelestica — Thu, 03 May 2018 08:36:03 GMT

Well, I am trying to test the functionalities of the board, and it would make easy to know if that bit works properly. I will measure if the result of the state change has occurred, then. Thank you very much.

RE: nRF52840 GPIO definition issue

Einar Thorsrud — Thu, 03 May 2018 07:13:26 GMT

A GPIO pin can only be configured to be in or out, not in and out. But why would you want that in the first place? If you have set or cleared a gpio output pin, you know it's state, so why do you want to read it?

That said, if you you change a pin to an input it will be in a high impedance state (not driven high or low), regardless of what it was before when it was configured as an output.

RE: nRF52840 GPIO definition issue

adragocelestica — Wed, 02 May 2018 14:21:06 GMT

Hi,

Today I have managed to make the GPIOs work by redefining them as outputs when I set or clear them. However, after that I cannot successfully read the value of the GPIO. I imagine that I could define the GPIO as input before reading its state, but i don't know if when doing that the nRF52840 would keep driving the GPIO or I would have to inmediately redefine the GPIO as output and re-write its value, which doesn't look quite optimal. If you could clarify me how is the best method of doing that, it would save me a lot of time and trial-and-error. Thank you

RE: nRF52840 GPIO definition issue

Einar Thorsrud — Wed, 02 May 2018 12:01:19 GMT

Hi Alin,

Have you had any progress with this issue? I do not know anything about your code, but it seems more likely that there is a flaw in your application logic somewhere, and not with the GPIO mapping itself. Have you stepped through the code or added debug printouts that show the flow of your application, and when it changes the state of GPIOs?