https://devzone.nordicsemi.com/f/nordic-q-a/62283/qspi-writes-of-4-bytes-failHello: I am using the QSPI example on the NRF52840 dev board with the objective of implementing SPIFFS. After a lot of tinkering I believe this is not possible due to the fact that the QSPI seems to fail for reads/writes of less than 4 bytes. I founden-USTelligent Community 13Tue, 09 Jun 2020 14:45:41 GMThttps://devzone.nordicsemi.com/thread/254079?ContentTypeID=1Tue, 09 Jun 2020 14:45:41 GMT137ad170-7792-4731-bb38-c0d22fbe4515:7470059c-1f3b-414e-9db8-885cefb6764aEduardo Garcia<p>Thank you, understood. I will implement with SPI. It would be a significant modification to the library to adapt for word use. Thanks again!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/253820?ContentTypeID=1Mon, 08 Jun 2020 13:36:29 GMT137ad170-7792-4731-bb38-c0d22fbe4515:0e5f3519-bb0e-488c-bd4e-59bc899724ddSimonr<p>Hi</p> <p>Indeed, the QSPI is only able to read and write full words I.E. in multiples of 4 bytes. This is because the QSPI peripherals READ and WRITE SRC registers have to point to a word-aligned address and only works in 32-bit words, I.E. ending with 0x0, 0x4, 0x8, or 0xC. Please see <a href="https://infocenter.nordicsemi.com/index.jsp?topic=%2Fps_nrf52840%2Fqspi.html&amp;c&amp;anchor=register.WRITE.SRC">the documentation</a> for more information. I know this isn&#39;t much of a further explanation, but the fact is that the HW peripheral is not able to end at any other values.</p> <p>I think you will have to go for using normal SPI unless you&#39;re able to edit all messages to end with one of the mentioned values (you might be able to add empty bytes of data at the end of each transmission to make this happen).</p> <p>Best regards,</p> <p>Simon</p><div style="clear:both;"></div>