https://devzone.nordicsemi.com/f/nordic-q-a/106333/how-to-disable-swd-permanently-using-uicr-approtect-registerHi, In my project, I need to disable SWD permanently. Can I do it using UICR.APPROTECT? The following 2 pieces of information confused me : 1. infocenter.nordicsemi.com/index.jsp After UICR has been written, the new UICR configuration will onlyen-USTelligent Community 13Wed, 06 Dec 2023 01:24:11 GMThttps://devzone.nordicsemi.com/thread/459086?ContentTypeID=1Wed, 06 Dec 2023 01:24:11 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b11d58e6-f675-44f6-9551-a0400d848d4cJianPan<p>Thanks, Sigurd. That is very helpful..</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/458993?ContentTypeID=1Tue, 05 Dec 2023 14:06:26 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c6172a89-140e-4c7e-918f-52a4f77c0cbbSigurd<p>Hi!</p> <p>This&nbsp;APPROTECT.DISABLE is a separate register, is not directly part of UICR.</p> <p><img style="max-height:240px;max-width:320px;" src="https://devzone.nordicsemi.com/resized-image/__size/640x480/__key/communityserver-discussions-components-files/4/pastedimage1701784494116v1.png" alt=" " /></p> <p><a href="https://infocenter.nordicsemi.com/topic/ps_nrf52840/dif.html?cp=5_0_0_3_7">https://infocenter.nordicsemi.com/topic/ps_nrf52840/dif.html?cp=5_0_0_3_7</a></p> [quote user=""]Question 2. Is there a way to disable SWD permanently, by&nbsp;UICR.APPROTECT register or by HW change?[/quote] <p>Not completely. On nRF52840 a debugger could trigger a erase-all operation. On the nRF5340 however, there is an additional <a href="https://infocenter.nordicsemi.com/topic/ps_nrf5340/ctrl-ap.html?cp=4_0_0_7_9_1#ctrlap_erase">ERASEPROTECT </a><span>register.</span></p><div style="clear:both;"></div>