https://devzone.nordicsemi.com/f/nordic-q-a/44038/dfu-implementationPlease answer some questions below. “Application” and “SoftDevice” can be replaced by DFU, correct? Is Nordic DFU function inside “Module” (Orange colour part)? If question 2 is yes then the hardware flow control must be implemented by host righten-USTelligent Community 13Mon, 25 Feb 2019 13:22:48 GMThttps://devzone.nordicsemi.com/thread/172770?ContentTypeID=1Mon, 25 Feb 2019 13:22:48 GMT137ad170-7792-4731-bb38-c0d22fbe4515:6b27700b-c3f8-4705-8956-8f829a616916Hung Bui<p>Hi Nalin,&nbsp;</p> <p>1. Correct</p> <p>2. No, it&#39;s running on the application area. DFU function requires a bootloader. The bootloader is a special application that can run even before the softdevice and can execute the real application if there is no DFU needed.</p> <p>We have a short presentation on how DFU works here:&nbsp;<a href="https://devzone.nordicsemi.com/b/blog/posts/a-presentation-on-how-nrf51-dfu-works">https://devzone.nordicsemi.com/b/blog/posts/a-presentation-on-how-nrf51-dfu-works</a></p> <p>3. Which bootloader are you asking about ? UART DFU or BLE DFU ? If it&#39;s UART it&#39;s possible to do without hardware flow control but the bitrate should be low enough.&nbsp;&nbsp;&nbsp;</p><div style="clear:both;"></div>