https://devzone.nordicsemi.com/f/nordic-q-a/115453/compatibility-between-mbr-and-sdmentioned MBR is never updated. For nRF52840, MBR&#39;s contents between S140 SD 6.1.0 and 7.2.0 are different. The answer in is still valid? Old MBR (6.1.0) can support new SD (7.2.0). right?en-USTelligent Community 13Mon, 14 Oct 2024 13:24:38 GMThttps://devzone.nordicsemi.com/thread/506147?ContentTypeID=1Mon, 14 Oct 2024 13:24:38 GMT137ad170-7792-4731-bb38-c0d22fbe4515:3ead759a-6c44-4c59-9796-c993adf1ffb6Davis Zheng<p>Thanks for your answer and information!!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/506144?ContentTypeID=1Mon, 14 Oct 2024 13:19:10 GMT137ad170-7792-4731-bb38-c0d22fbe4515:0af6386c-52b5-46d2-91f0-0590b42e0a84Edvin<p>Hello,</p> <p>Yes, the MBR is backwards compatible, meaning the 7.2.0 softdevice will work with the MBR from 6.1.0. As far as I know, there is no limitation on how far back. As you say, the MBR is never updated during a DFU, and we have had many customers who have updated the softdevice from 6.1.0 to 7.2.0, and I have not seen any reports that it doesn&#39;t work.</p> <p>Best regards,</p> <p>Edvin</p><div style="clear:both;"></div>