https://devzone.nordicsemi.com/f/nordic-q-a/108260/nrf51822-ble-firmware-stack-issueDear Sir/Madam, We are working on nRF51822 chip for BLE application. We are facing the problem and following steps we followed: - First there were no examples of 51822. We are using 51422 examples (pca10028). If there will be any specific exampleen-USTelligent Community 13Tue, 13 Feb 2024 12:03:15 GMThttps://devzone.nordicsemi.com/thread/468580?ContentTypeID=1Tue, 13 Feb 2024 12:03:15 GMT137ad170-7792-4731-bb38-c0d22fbe4515:461d4625-ee53-4456-b7b4-1d8d89fdb6b0Vidar Berg<p>Hello,</p> <p>Please note that the nRF51 series is not recommended for new designs. I strongly recommend considering a newer chip model for your project. Regarding the differences between the 51822 and 51422, the only&nbsp;difference is that the latter is licensed for use with the ANT protocol stack, which&nbsp;is not relevant if you&#39;re using BLE.&nbsp;What is more relevant is what package variant you have. The nRF51422 on the nRF51 DK&nbsp;has the xxAC package, which&nbsp;has 256K of flash and 32K of RAM. For an overview of the different memory variants, please see the document&nbsp;<span>&#39;</span><a title="nRF51822 IC revisions and variants" href="https://infocenter.nordicsemi.com/topic/comp_matrix_nrf51/COMP/nrf51/nRF51822_ic_revision_overview.html?cp=6_0_2">nRF51822 IC revisions and variants</a><span>&#39;. If you are using a different memory variant, it is necessary to adjust the linker settings in the SDK projects accordingly.</span></p> <p><span>Best regards,</span></p> <p><span>Vidar</span></p><div style="clear:both;"></div>