mqtt

Good morning everyone, I'm trying to use the MqttClient within a WebSocket to create a simple logger that displays the topics passing through my Mosquitto broker via a web page. In the 'websocket_connect' event, I invoke the connect function to the MQTT, but I never receive the success or...

Hi Everyone, I am working on a project where I have a raspberry pi 4B where I have a b4j app running which communicates with a 32 channel Analog to Digital Converter we designed and built at work, the communication is via I2C protocol, this part works very well as far as I have been able to...

Hi, I read several posts and studied several examples but I can't connect my ESP8266 D1 mini to the broker. Sub Process_Globals Private Broker As MqttBroker Private Client As MqttClient Private ESPTopic As String = "ESP8266_1" Private Name As String = "SKIKK_1" End Sub Sub...

In the chat example, messages from one client are shown to all clients. How can you send a message to only one specific client if you know his name.

It is possible to use multiple user subscriptions per client. I want to be able to receive different types of messages, my task is wider than just chat. The client must receive different objects and process them differently. Private Sub client_Connected (Success As Boolean) If Success=True...

Having to allow the communication of a mqtt server by some mobile devices external to the local network, what are the only possibilities to protect the connection/communication between client and mqtt broker so that any intruders cannot disturb the communications?

Hello, I am new MQTT technology and therefore I want to know will MQTT allow me to use Wifi for messaging? This option can to collect information from android devices near the server (broker) by WiFi? Security tools in modern versions of android will allow me to solve my problem? Where can I...

Hello all, I am writing an app which uses MQTT, and I find a problem with "wait for". In an activity "info" I must collect several data from MQTT: every datum is asked for by publishing a topic and waiting for the reply. I would like to write several lines like: Sub Activity_Create(FirstTime...

Hello I want to use an encryptes MQTT connection in all my B4J projects. My local Mosquitto MQTT broker has been configured to use TLS with a server and client certificate, both self signed, but there is no option in the library to parse the certificate to setup the connection. I followed this...

Hi Here a sample program to control/monitor 8+8 digital Out-Inp, plus an I2C ADC. The program use the MQTT protocol. This program is an evolution of the previous one I posted. This version add the monitor of 8 digital Input and four analog input read by ADC (ADS1115).

Hi everyone i'm trying to use MQTT for the first time. I follwed this example. It connects succesfully but unfortuntely when I receive a message this error shows up Error occurred on line: 96 (B4XPage_Details) Error decompressing data Stack Trace: ( CoreFoundation...

Hi everyone, I attached simple example for streaming audio from B4A to B4J over internet using MQTT. Enjoy without limitations of Server/Client problems over internet such as ISP block. You can use this approach to create a lot of things such as Radio station, voice call, etc ...

Hi, I have a problem with mqtt library version 1.01 I have to connect via ssl connection to my mosquitto server; I followed the tutorial at this link https://www.b4x.com/android/forum/threads/b4x-mqtt-ssl-and-self-signed-certificates.100973/#content, but I have these errors...

Hello everyone! I must make an app (to be more specific 2 apps Android & IOS). I want to connect with AWS MQTT Broker, via MQTT protocol. I made a lot of tries to achieve a connection (first of all, and then publish-subscribe to a topic), with no success. Is there someone, who has used AWS, to...

Hello I'm using mqtt to subscribe a large number of topics, i noticed that sometimes i get the "Client connected (32100)" error. When this happens, the client disconnects without triggering the _disconnected event. This seems to happen sometimes when receiving multiple topics after...

I was just trying to make my first project with B4R. Also, I was a newbie in microcontroller programming. In this my first project, I make a dashboard in Node-RED to display a value from the ESP32 and to control the blue LED on ESP32. The value had been successfully sent, but until now the...

I am trying to connect to a data streaming API and below is an extract from the API documentation (in red italics). Connection to the message broker is made using a Websocket connection and the message broker makes use of the MQTT protocol. So my initial obstacle is that I understand that...

I have a program, made with B4J (ver. 8.50) which is active 24 hours a day on Windows 10 professional pc This program connects with a mqtt broker, Mosquitto, to 'read' the commands that some phones send, commands that must be executed on the pc The program works correctly, but using the Windows...

Vorrei passare su pc un file di testo che si trova nella memoria Android Smartphone e pc comunicano via mqtt L'invio e la ricezione avvengono correttamente Ma, lato ricezione, uso questo codice: Private Sub mqtt_MessageArrived (Topic As String, Payload() As Byte) Dim out As OutputStream =...

This updates the PubSubClient to v2.8 These functions have been added to B4R: IsConnected SetBufferSize SetKeepAlive SetSocketTimeout You must exchange the included folder and xml file in B4R folder: C:\Program Files (x86)\Anywhere Software\B4R I hope that this could be added to B4R, so it...