https://devzone.nordicsemi.com/f/nordic-q-a/53855/use-spi-master-within-nus-data-handlerHi, I can use the SPI master functionality within nrf_drv_spi.c/.h just fine (i.e. calls from main) until I connect to my nRF52840 and utilize NUS. If I try to issue a nrf_drv_spi_transfer() call from within my NUS data handler (i.e. when handing incomingen-USTelligent Community 13Thu, 31 Oct 2019 00:02:56 GMThttps://devzone.nordicsemi.com/thread/217637?ContentTypeID=1Thu, 31 Oct 2019 00:02:56 GMT137ad170-7792-4731-bb38-c0d22fbe4515:ead9bd37-d41a-4598-b5f6-48a8aabf31faMark J<p>I was able to resolve this by simply scheduling a handler on the main thread from the NUS data hander. There may also be a way to resolve through priority changes, but I will leave it to a Nordic expert to suggest such a change.</p><div style="clear:both;"></div>