https://devzone.nordicsemi.com/f/nordic-q-a/77328/trouble-configuring-larger-mtu-on-zephyrHello, I&#39;m trying to configure a larger MTU because I need to read/write GATT characteristics with size 216. I&#39;ve already tried setting CONFIG_BT_ATT_PREPARE_COUNT to allow &quot;long writes&quot;, however, this is not a solution for me, because in this caseen-USTelligent Community 13Sat, 10 Jul 2021 00:48:13 GMThttps://devzone.nordicsemi.com/thread/319466?ContentTypeID=1Sat, 10 Jul 2021 00:48:13 GMT137ad170-7792-4731-bb38-c0d22fbe4515:5cfb70f2-c339-41cb-857e-d0968f65d336Dani&#235;l Schenk<p>I managed to get it working now by removing these two settings.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/319465?ContentTypeID=1Sat, 10 Jul 2021 00:36:57 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b1ca7db2-094b-43f1-b5b9-cbd7911cb92cDani&#235;l Schenk<p>Update: that was using NCS 1.5.0. I updated to NCS 1.6.0, now I get the following issues:</p> <p><pre class="ui-code" data-mode="text">warning: attempt to assign the value &#39;247&#39; to the undefined symbol BT_L2CAP_RX_MTU warning: attempt to assign the value &#39;y&#39; to the undefined symbol SPI_0 </pre></p> <p>I&#39;ve been trying to go through Zephyr release notes to find what happened to these settings, but without results.</p><div style="clear:both;"></div>