https://devzone.nordicsemi.com/f/nordic-q-a/126977/9151-doesn-t-respond-to-at-xmqttcfg-but-does-respond-to-at-xmqttconHi all, I&#39;ve been troubleshooting my 9151 feather and have run into some issues with very specific AT commands. I&#39;m trying to connect to an MQTT broker through AT commands over a UART interface with another processor. I&#39;ve got the basics all up anden-USTelligent Community 13Thu, 12 Feb 2026 12:47:26 GMThttps://devzone.nordicsemi.com/thread/561011?ContentTypeID=1Thu, 12 Feb 2026 12:47:26 GMT137ad170-7792-4731-bb38-c0d22fbe4515:65b3ed3d-459b-4b95-ba0e-4512e2ce4fea&#216;yvind<p>Happy to help! Let us know if there are any other issues. Good luck testing it further <span class="emoticon" data-url="https://devzone.nordicsemi.com/cfs-file/__key/system/emoji/1f642.svg" title="Slight smile">&#x1f642;</span></p> <p>Kind regards,<br />Øyvind</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/561001?ContentTypeID=1Thu, 12 Feb 2026 12:02:42 GMT137ad170-7792-4731-bb38-c0d22fbe4515:88ddc1a5-3d3d-4f95-97b0-30f05de2754eJoe01<p>Sweet that seems to have fixed it. I appreciate the help.&nbsp;</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/560997?ContentTypeID=1Thu, 12 Feb 2026 11:49:30 GMT137ad170-7792-4731-bb38-c0d22fbe4515:d9b69057-6434-4dc2-9870-8637a952fc19&#216;yvind<p>What version of the Serial Modem are you running on your device?</p> [quote user="Joe01"]AT#XMQTTCON=1,&quot;&quot;,&quot;&quot;,&quot;tcp://test.mosquitto.org&quot;,1833[/quote] <p>This seems to be the culprit. The URL should be test.mosquitto,org i.e <code>AT#XMQTTCON=1,&quot;&quot;,&quot;&quot;,&quot;test.mosquitto.org&quot;,1833</code></p> <p></p> <p>Let me know how that works for you</p> <p>Kind regards,</p> <p>Øyvind</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/560994?ContentTypeID=1Thu, 12 Feb 2026 11:34:37 GMT137ad170-7792-4731-bb38-c0d22fbe4515:19895423-f8c0-4bd4-be8a-9164515f9ed1Joe01<p>Hi, AT#XMQTTCFG returns OK on submit, but when polled, (AT#XMQTTCFG?) gives the correct name and setup. AT#XMQTTCON just returns ERROR. Here&#39;s a brief log below with echo enabled.&nbsp;</p> <div> <blockquote> <pre>AT%XAPNSTATUS? </pre> </blockquote> </div> <blockquote> <div> <pre>%XAPNSTATUS: </pre> </div> <div> <pre></pre> </div> <div> <pre>OK </pre> </div> <div> <pre></pre> </div> <div> <pre>AT%XAPNSTATUS=1,&quot;infisim.iot&quot; </pre> </div> <div> <pre>OK </pre> </div> <div> <pre></pre> </div> <div> <pre>AT#MQTTCFG? </pre> </div> <div> <pre>+CME ERROR: 0 </pre> </div> <div> <pre></pre> </div> <div> <pre>AT#XMQTTCFG? </pre> </div> <div> <pre>#XMQTTCFG: &quot;KuiperDevelopmentBoard&quot;,60,1 </pre> </div> <div> <pre></pre> </div> <div> <pre>OK </pre> </div> <div> <pre></pre> </div> <div> <pre>AT#XMQTTCON? </pre> </div> <div> <pre>#XMQTTCON: 0 </pre> </div> <div> <pre></pre> </div> <div> <pre>OK </pre> </div> <div> <pre></pre> </div> <div> <pre>AT#XMQTTCON=1,&quot;&quot;,&quot;&quot;,&quot;tcp://test.mosquitto.org&quot;,1833 </pre> </div> <div> <pre>ERROR </pre> </div> <div> <pre></pre> </div> <div> <pre>AT#XMQTTCON=1 </pre> </div> </blockquote> <div> <blockquote> <pre>ERROR<br /><br /></pre> </blockquote> </div><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/560968?ContentTypeID=1Thu, 12 Feb 2026 06:05:30 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c0a519bf-a704-4782-b553-645ca6ae80fe&#216;yvind<p>Hello Joe,&nbsp;</p> <p>What exactly does #X<span>MQTTCFG return in your case? This command&nbsp;allows you to <a href="https://docs.nordicsemi.com/bundle/addon-serial_modem-v0.3.0/page/app/at_mqtt.html#mqtt_configure_xmqttcfg">configure the MQTT client</a> before connecting to a broker, and will return only OK. Can you please provide a full log from your side?</span></p> <p><span>Kind regards,<br />Øyvind</span></p><div style="clear:both;"></div>