Fast encoder sampling rate for nRF52xx

[Omri Friedman]

We need to sample two digital inputs GPIOs at rate of 100khz-1mhz. How can we do that? The QDEC is only good for up to 128us (~7khz) which is too slow for us. Is there a way to sample GPIO with DMA? If not, is there a way to do that without using interrupt every 10us?

[Sigurd]

Hi,

You should be able to do this using GPIOTE, PPI and a TIMER in counter mode. See this post for some more information.

[Omri Friedman]

cant i clock the the counter in rising & falling mode instead of just rising edge? if i have to manually change direction then i may just as well use a simple interrupt every rising/falling and read the gpio's to a buffer in the interrupt (simulate DMA). The interrupt just reads io to buffer and thats it.