https://devzone.nordicsemi.com/f/nordic-q-a/34329/programming-nrf51822-on-a-custom-board-using-nrf52840dkHello, Is it possible to program nRF51822 with nRF52DK (PCA10056) ? Currently I am trying to program my custom beacon (nRF51822) connected via SWD P20 header. I am using SDK 12.3.0 and Keil uVision 5. I have tried to upload radio_test example fromen-USTelligent Community 13Tue, 15 May 2018 09:03:46 GMThttps://devzone.nordicsemi.com/thread/131991?ContentTypeID=1Tue, 15 May 2018 09:03:46 GMT137ad170-7792-4731-bb38-c0d22fbe4515:3d381166-ba54-408e-a213-ceb4bc24b3b7Kamil<p>Hi Vidar, </p> <p>I was a bit confused with this, but now I&#39;ve understood what went&nbsp; wrong. As you&#39;ve said, I had to upload example from pca10028 which covers the nRF51 series. Thank you very much for your reply, it helped me a lot!</p> <p>Greetings!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/131971?ContentTypeID=1Tue, 15 May 2018 08:07:12 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a682c6ed-e820-445a-a6dc-c95033142324Vidar Berg<p>Hi Kamil,</p> <p>yes, you need to change the programming target to nRF51822. Correct target configuration will be set if you use a project configured for the 51 series (i.e., pca100028 projects).&nbsp;</p><div style="clear:both;"></div>