https://devzone.nordicsemi.com/f/nordic-q-a/87251/about-nrf52832-write-flash-by-jlinkhi ，i want write flash by jlink，eg：write val 0xaaffffff to addr 0x76000, only write 4byte. but when i write, err &quot;flash not erase&quot; occurred， I don&#39;t want to erase this flash because there are other data on this page. So I want to ask if there is aen-USTelligent Community 13Mon, 25 Apr 2022 09:21:15 GMThttps://devzone.nordicsemi.com/thread/364648?ContentTypeID=1Mon, 25 Apr 2022 09:21:15 GMT137ad170-7792-4731-bb38-c0d22fbe4515:8c0aa16c-ad86-462f-a922-c49317b382d9Hung Bui<p>Hi,</p> <p>Just as Vasiliy said. You need to erase the&nbsp;flash area before you write to it.&nbsp;</p> <p>If you want to keep the content of the flash page, you would need to read the content out, modify what&nbsp; you want to change and then erase and write the new content back.&nbsp;</p> <p>If you only change from 1 to 0 on the bit, and don&#39;t want to erase you can try using nrfjprog --memwr . This tool won&#39;t require the whole flash page to be erased to write.&nbsp;</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/364551?ContentTypeID=1Sat, 23 Apr 2022 12:17:26 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e5679d78-32b4-4175-a8fe-f9c7430a5379qwertynoon<p>You must to erase page before flashing. While flash nrf52 can set 1 to 0 and can not to set 0 to 1. thats why first you erase page (erase process set 0 to 1) and then you can flash your data</p><div style="clear:both;"></div>