https://devzone.nordicsemi.com/f/nordic-q-a/57329/optimize-the-serial-throughput-with-usb_cdc_acmHello, guys! We are working with SDK 15.0.0 and nRF52840 SoCs. There is a need to transfer a few MBytes of data from the PC to nRF52840 and then on external flash memory. We used usb_cdc_acm for communication between nRF52850 and PC. What we experienceen-USTelligent Community 13Tue, 04 Feb 2020 10:45:27 GMThttps://devzone.nordicsemi.com/thread/232515?ContentTypeID=1Tue, 04 Feb 2020 10:45:27 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b0c1eed7-db65-4455-96d5-2b1a2b659020bojan<p>Thanks for clarification, <a href="https://devzone.nordicsemi.com/members/turboj">Turbo J</a>. </p> <p>Cheers!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/232424?ContentTypeID=1Mon, 03 Feb 2020 18:57:39 GMT137ad170-7792-4731-bb38-c0d22fbe4515:624b92c2-f988-4e13-8237-4d3f7258775cTurbo J[quote userid="76830" url="~/f/nordic-q-a/57329/optimize-the-serial-throughput-with-usb_cdc_acm"] if we change the baud rate of the data transfer on the PC side. 115200, 230400, 460800... they all transfer the data for the same amount of time.[/quote] <p>Expected behavior for USB-CDC. The baud rate is just ignored unless a physical UART is present.</p> <p></p> <p>That also means there is not much you could do exept for expensive double-buffering (reading the next page from USB while while a page is being erased/written).</p><div style="clear:both;"></div>