mqtt

Star-Dust, The example you made is so fantastic. Thank you It settled the problem I was having with FCM. Please can you tell me how to send an Image - from Phone to Desktop - using the same MQTT method. You said about adding a Transmission Protocol...

I got a sun roof here. One of those with pivoting slats. The hardware is from a company in the Czech Republic. The controls are from Italy: Teleco. Teleco makes several remote control systems, so this project may be used differently. The control box has an arm processor. You can connect several...

I wish to incorporate an MQTT client into my B4A and B4I mobile apps using Amazon's "IoT Core" cloud based MQTT broker. I've successfully used other MQTT clients/brokers that authenticate using username and password, but AWS use X.509 certificates which I'm finding a lot harder to understand...

I have several remote Linux "boxes" collecting sensor data that I occasionally need to SSH into for troubleshooting, etc. The problem is that all of these boxes are behind firewalls as is expected so it's impossible to SSH or SCP into the boxes without having the network administrator open Port...

Why this is not working? ' code .... Wait For mqttclient_MessageArrived(Topic As String, Payload() As Byte) ' rest of code .... I can't go to rest of code after publishing and should receiving msg!

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...