Hello mainul, I am able to send data to mqtt server successfully with the below configuration. static MQTT_Connect_T MqttConnectInfo = { .ClientId = "XDS_FS", .Username = APP_MQTT_USERNAME, .Password = APP_MQTT_PASSWORD, .BrokerURL = "broker.hivemq.com", .BrokerPort = 1883, .CleanSession = true, .KeepAliveInterval = 100, };/**< MQTT connect parameters */ Attached Workbench log for reference, INFO | XDK DEVICE 1: Successfully set IP using DHCP INFO | XDK DEVICE 1: Trying to connect with WiFi network... INFO | XDK DEVICE 1: Successfully removed obsolete profiles INFO | XDK DEVICE 1: Added new WLAN profile INFO | XDK DEVICE 1: Successfully reset obsolete connection policy INFO | XDK DEVICE 1: Successfully set new connection policy INFO | XDK DEVICE 1: Started collecting WLAN Rx Statistic INFO | XDK DEVICE 1: IP address of device 192.168.43.50 INFO | XDK DEVICE 1: Mask 255.255.255.0 INFO | XDK DEVICE 1: Gateway 192.168.43.1 INFO | XDK DEVICE 1: DNS 192.168.43.1 INFO | XDK DEVICE 1: Connected to WPA network successfully INFO | XDK DEVICE 1: MqttEventHandler : Event - 0 INFO | XDK DEVICE 1: ServalMqttAgent:SubscribeToTopic - Subscribing to topic: BCDS/XDK110/example/out, Qos: 1 INFO | XDK DEVICE 1: MqttEventHandler : Event - 8 INFO | XDK DEVICE 1: MqttEventHandler : Event - 14 INFO | XDK DEVICE 1: AppMQTTSubscribeCB : #1, Incoming Message: INFO | XDK DEVICE 1: Topic: BCDS/XDK110/example/out INFO | XDK DEVICE 1: Payload: INFO | XDK DEVICE 1: """ INFO | XDK DEVICE 1: Environmental Data - INFO | XDK DEVICE 1: Humidity : 54 INFO | XDK DEVICE 1: Pressure : 96257 INFO | XDK DEVICE 1: Temperature : 30.181000ø INFO | XDK DEVICE 1: """ INFO | XDK DEVICE 1: MqttEventHandler : Event - 15 INFO | XDK DEVICE 1: MqttEventHandler : Event - 14 Reason why you were getting "asserted at Filename ./../Libraries/ServalStack/3rd-party/ServalStack/api/Serval_StringDescr.h , line no 180 " error was, You have removed below 2 parameter from the mqtt structure, .Username = APP_MQTT_USERNAME, .Password = APP_MQTT_PASSWORD, Could you please include back those parameter and Could you Clean the application and Build and Flash the application into XDK. XDK will be connected to mqtt server. I Hope this will solve your problem.
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