https://devzone.nordicsemi.com/f/nordic-q-a/91474/nrf52-dk-rbp-gets-enabled-without---rbp-while-flashing-with-nrfjprogHi, I am trying to flash nrf52840 dk board with open thread binaries. I see that, sporadically the device gets readback protection enabled. I use the following command to flash hex files: nrfjprog -f nrf52 -s &lt;serialid&gt; --verify --chiperaseen-USTelligent Community 13Wed, 31 Aug 2022 07:55:33 GMThttps://devzone.nordicsemi.com/thread/384057?ContentTypeID=1Wed, 31 Aug 2022 07:55:33 GMT137ad170-7792-4731-bb38-c0d22fbe4515:1b31198e-9935-486a-a29b-ef71303a3dbeH&#229;kon Alseth<p>Hi,</p> <p>&nbsp;</p> <p>You are most likely using revision 3 devices, which include approtect hardening as per this informational notice #142:</p> <p><a href="https://infocenter.nordicsemi.com/pdf/in_142_v1.1.pdf?cp=4_2_2_3">https://infocenter.nordicsemi.com/pdf/in_142_v1.1.pdf?cp=4_2_2_3</a></p> <p>&nbsp;</p> <p>The fix for this is to use newer startup files (MDK files), which are downloadable from here:</p> <p><a href="https://www.nordicsemi.com/Products/Development-tools/nRF-MDK">https://www.nordicsemi.com/Products/Development-tools/nRF-MDK</a></p> [quote user=""]Also, I remember reading about rbp somewhere,&nbsp;UICR registers have&nbsp;limited number of writes&nbsp;and would this be harmful to recover the device every time after RBP is enabled?[/quote] <p>As per &quot;Endurance&quot; specification, the chip itself is specified to work with &gt; 10k write/erase cycles:</p> <p><a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/abs_max_ratings.html?cp=4_2_0_4#abs_max_ratings">https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/abs_max_ratings.html?cp=4_2_0_4#abs_max_ratings</a></p> <p>&nbsp;</p> <p>Kind regards,</p> <p>Håkon</p><div style="clear:both;"></div>