Simultaneous use of GPIOTE and other peripheral

RE: Simultaneous use of GPIOTE and other peripheral

Jared — Mon, 22 Mar 2021 13:47:44 GMT

Hi,

I might have misunderstood you a bit. Anyways, I did a quick test by merging the nrfx_SPIM example and the pin_change_int example. The modified example would toggle a LED via GPIOTE every time the MISO line would toggle. I think that this would show that it's indeed possible to trigger a task via GPIOTE from a Pin that is already used by SPIM as MISO.

regards

Jared

RE: Simultaneous use of GPIOTE and other peripheral

Gauthier — Thu, 18 Mar 2021 08:38:47 GMT

It seems that your work-around for Errata 58 does something similar: connect an SPI pin (SCK, in this case an output, while in my it's an input) to GPIOTE, which then through PPI triggers an SPI task (STOP).

https://infocenter.nordicsemi.com/index.jsp?topic=%2Ferrata_nRF52840_EngB%2FERR%2FnRF52840%2FEngineeringB%2Flatest%2Ferr_840_fixed.html&cp=4_0_1_4_2

I'm not sure what you refer to with "switching", I just want to start the transfer on an incoming flank.

RE: Simultaneous use of GPIOTE and other peripheral

Jared — Tue, 16 Mar 2021 08:43:48 GMT

This is an unusual use case, and I don't think it has been tested by us. In general we recommend assigning only one peripheral per pin.

Are you doing the switch between transactions or during a transaction? If it's the former then you can use the CS signal instead to trigger the switch, that should give you a bit more time. If it's the latter then I don't think that it would be doable. Do you know what IRQ that is blocking the switch when it's failing?

RE: Simultaneous use of GPIOTE and other peripheral

Gauthier — Fri, 12 Mar 2021 16:05:17 GMT

Not trying to drive a GPIO, but to use as an input.

RE: Simultaneous use of GPIOTE and other peripheral

Jared — Fri, 12 Mar 2021 14:42:58 GMT

Hi,

[quote user=""]

Is it possible (and supported) to have the same pin configured as GPIOTE input, and SPI miso *at the same time*, and get the PPI to react on GPIOTE and start the SPI transfer?

[/quote]

We recommend only having one peripheral driving one GPIO pin at a time. However, you could use two pins and connect them together externally.

regards

Jared