https://devzone.nordicsemi.com/f/nordic-q-a/42235/is-this-a-mistakeI am learning UART DFU and I found this: https://www.nordicsemi.com/DocLib/Content/SDK_Doc/nRF5_SDK/v15-0-0/lib_bootloader#lib_bootloader_memoryen-USTelligent Community 13Tue, 08 Jan 2019 10:56:07 GMThttps://devzone.nordicsemi.com/thread/164490?ContentTypeID=1Tue, 08 Jan 2019 10:56:07 GMT137ad170-7792-4731-bb38-c0d22fbe4515:f66c053b-4b59-49d7-8f50-737e71db1385Susheel Nuguru<p>There is a typo in the application area side. The softdevice ends at 0x00026000 for S140. So the application are should start at the same address 0x00026000 (not 0x2000000) Which makes the size 840KB (not 864KB)</p> <p>Then you math will add up</p> <p><span>4 + 4 + 24 + <strong>840</strong> + 148 + 4&nbsp;= 1024</span></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/164460?ContentTypeID=1Tue, 08 Jan 2019 09:16:11 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e8887c27-e7b3-47d8-afbe-28791795f00fz7z8king<p>4 + 4 + 24 + 864 + 148 + 4 = 1048k, But&nbsp;<span>nRF52840 has a flash size of 1024 kB</span></p><div style="clear:both;"></div>