Timer doesn't trigger if pin is held low

RE: Timer doesn't trigger if pin is held low

SmallerPond — Tue, 31 Aug 2021 01:39:29 GMT

Yes, this fixes everything (as I said) but I guess it seems curious to me that nrfx_gpiote_uninit() doesn't clear the interrupts on the way out under the assumption that I am uninitializing it because I do not plan on using it at the time. I think the error was in my assumption, but I guess now I am just curious what the assumptions are for the GPIOTE uninitialization. I guess you figure that it's up the developer to decide if she wants to check for a final interrupt after uninitialization?

RE: Timer doesn't trigger if pin is held low

Einar Thorsrud — Fri, 27 Aug 2021 13:19:58 GMT

Hi,

If an interrupt is active it needs to be cleared. It seems that has been forgotten here?

RE: Timer doesn't trigger if pin is held low

SmallerPond — Fri, 27 Aug 2021 03:27:20 GMT

After re-reading my post, I thought to take a look at the GPIOTE registers to see if there might be a clue there. It seems that before we run our activity, all of the EVENTS_IN[n], EVENTS_PORT, INTENSET, INTENCLR, and CONFIG[n] registers are set to 0. However, after disabling GPIOTE using nrfx_gpiote_uninit(), I see that both INTENSET and INTENCLR simultaneously have PORT (bit 31) set to 1. Writing a 1 to INTENCLR bit 31 fixes my issue. Not sure if this is intended?