https://devzone.nordicsemi.com/f/nordic-q-a/40516/j-flash-secure-chipHi. I just started with nRF52840. When I use J-flash for STM, normally it proveds &#39;secure chip&#39; as below. But when I choose nRF52840, I can&#39;t see &#39;secure chip&#39; activated as below.. How can I activate it? I need your help.en-USTelligent Community 13Fri, 16 Nov 2018 04:57:50 GMThttps://devzone.nordicsemi.com/thread/157627?ContentTypeID=1Fri, 16 Nov 2018 04:57:50 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e02f5248-5b91-44ad-bd30-3297f454e5cfroger.k<p>Dear Hung Bui. Thank you very much.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/157547?ContentTypeID=1Thu, 15 Nov 2018 14:29:06 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a18af1cb-5614-4d4b-b0d2-b398c47434b6Hung Bui<p>Hi Kwak,</p> <p></p> <p>I don&#39;t think we support the &quot;Secure Chip&quot; feature on JFlash, it&#39;s a feature on ST chip.</p> <p>On our chip you can activate protection of SWD access by using APPROTECT, this requires you to write to a register in the UICR. Please have a look at section 4.8 in the nRF52840 Product Spec and look for APPROTECT. The only way to disable APPROTECT is to issue an erase all to the chip.</p><div style="clear:both;"></div>