https://devzone.nordicsemi.com/f/nordic-q-a/16733/fail-flash-bootloader-by-st-linkHere My device (chip nrf51822_xxAA) exist softdevice 8.0.3 and BLE uart application work fine which flash by the ST-link in Keil MDK(5.20). Now I try to add bootloader to my device from the example project of &quot;bootloader\pca10028\dual_bank_ble_s110en-USTelligent Community 13Fri, 30 Sep 2016 10:02:05 GMThttps://devzone.nordicsemi.com/thread/63988?ContentTypeID=1Fri, 30 Sep 2016 10:02:05 GMT137ad170-7792-4731-bb38-c0d22fbe4515:eab1f17e-ecda-4ce3-b574-5ede6dc4cdacVidar Berg<p>Is there a command line tool for this programmer? In that case you should be able to set the bootloader&#39;s start address manually (write start address to 0x100010014). As you have seen, the flash algorithm in Keil does not support the UICR section, and thus skipping it despite it being a part of the built image.</p> <p>Note that the bootloader will not be started by the MBR unless you have set this register =&gt; <a href="http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.s132.sds/dita/softdevices/s130/mbr_bootloader/mbr_sd_reset_behavior.html?cp=2_3_0_0_11_2">MBR reset behavior</a></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/63987?ContentTypeID=1Thu, 29 Sep 2016 11:48:55 GMT137ad170-7792-4731-bb38-c0d22fbe4515:914302f7-4b3a-42a7-8633-86e15da228c9bjorn-spockeli<p><a href="https://devzone.nordicsemi.com/blogs/485/programming-nrf51-with-st-link-uvision/">This</a> blog post explains how to program nRF51s with ST-Link. I am unsure if the nRF51xxx External Connection programming algorithm allows you to program the UICR registers. If not, then you can use the debug out port(P19) on the nRF51 DK to program external nRF51s with the JLink OB programmer, see <a href="https://devzone.nordicsemi.com/question/42354/programming-other-nrf51822s-using-nrf51-dk/">this</a> post.</p> <p>-Bjørn</p><div style="clear:both;"></div>