https://devzone.nordicsemi.com/f/nordic-q-a/41392/i-can-not-communicate-at-1000-hz-with-spi-communicationHi, I am using nRF_SDK_15.0.0_a53641 and writing a program with keil. I am now trying to write to the SD card at 1000 Hz (1 ms) by combining &quot;fatfs example&quot; and &quot;app timer example&quot;. However, communication is possible only at about 10 Hz. Is thereen-USTelligent Community 13Mon, 10 Dec 2018 12:23:43 GMThttps://devzone.nordicsemi.com/thread/160972?ContentTypeID=1Mon, 10 Dec 2018 12:23:43 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a734a0c5-1514-4b31-bd2b-08639fa91f1fy001<p>It was caused by looping f_open in fatfs.</p> <p>f_open was described outside the loop, and within the loop it was solved by describing only f_write.</p><div style="clear:both;"></div>