https://devzone.nordicsemi.com/f/nordic-q-a/1762/getting-started-with-nrf51822-for-your-own-hardwareI found that &quot; The nRF51822 is built around a 32-bit ARM Cortex M0 CPU&quot;. On the page of Keil ( www.keil.com/.../4803.htm) is written that I can use either &quot;J-link ARM&quot; offered by Nordic or &quot;U-link me&quot; JTAG Debuggers. &quot;U-link me&quot; is low cost solution.en-USTelligent Community 13Tue, 04 Mar 2014 15:07:15 GMThttps://devzone.nordicsemi.com/thread/7708?ContentTypeID=1Tue, 04 Mar 2014 15:07:15 GMT137ad170-7792-4731-bb38-c0d22fbe4515:51ed8792-76af-4a7f-8a3f-304734be7c03Ole Morten<p>It should be perfectly possible to program an nRF51822 using the U-link from Keil directly, but our PC tools (nrfjprog and nRFgo Studio) only supports the Segger&#39;s. You will therefore not be able to download a softdevice to your chip, so I&#39;d strongly recommend you to make sure to also have a J-Link of some kind for this.</p> <p>Remember that <a href="https://devzone.nordicsemi.com/index.php/what-s-the-difference-between-nrf51822-evaluation-and-development-kits">the Development Kit contains a J-Link</a> you can use to program also your custom boards.</p><div style="clear:both;"></div>