https://devzone.nordicsemi.com/f/nordic-q-a/6841/softdevice-internal-error-in-s120-v1-0-1Devzone, I&#39;ve been working on a central device based on the project &#39;ble_app_multilink_central&#39; and have encountered an error originating from within the softdevice of 0xdeadbeef in ll_master.c &lt;2274&gt;. The error seems altogether spontaneous- i.e. neveren-USTelligent Community 13Wed, 06 May 2015 09:02:42 GMThttps://devzone.nordicsemi.com/thread/24111?ContentTypeID=1Wed, 06 May 2015 09:02:42 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e04aa8d4-d3e1-4480-be60-59623d9e1485Petter Myhre<p>QFAAC0 is the first revision of the nRF51 chip, and unfortunately it is not compatible with the S120 1.0.1 SoftDevice.</p> <p>This information can be found in the nRF51 Series Compatibility Matrix, found <a href="https://www.nordicsemi.com/eng/Products/ANT/nRF51422#Downloads">here</a>.</p> <p>You can use the tables on Page 3 and 4 to figure out what revision you have, and then use the table on Page 6 to figure out which SoftDevices and SDKs that are compatible with that revision.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/24109?ContentTypeID=1Mon, 04 May 2015 14:38:20 GMT137ad170-7792-4731-bb38-c0d22fbe4515:2e22e2bf-b2af-4abc-af30-bde846c65b78Tyler<p>Certainly- we&#39;re using the QFAAC0 variant.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/24110?ContentTypeID=1Sat, 02 May 2015 19:46:25 GMT137ad170-7792-4731-bb38-c0d22fbe4515:2a01ae8c-4d37-4ade-93e2-ee181b8418bcUlrich Myhre<p>Could you please add what hardware revision you are running this on?</p><div style="clear:both;"></div>