Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [mqtt]

15 questions
8
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1 answer

Lowest latency out of the 802.11 Wi-Fi standards

I'm making a project using an Arduino and an ESP8266 module running the esp-link firmware - which gives me the ability to use MQTT for controlling the Arduino. I'd looked at something like an XBee module instead - but they're so damn expensive…
seanlano
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1 answer

MQTT Broker vs Server

I am trying to learn MQTT technology. What I understand so far, is that MQTT is based on a 'Broker' that does the 'Publish and Subscribe' of messages and topics. I wonder if it's another name for 'Server' in common terms? If it's like that, then why…
scico111
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Send data to MQTT broker using SIM800 and ESP32

I'm working on a project in which I need to send data to an MQTT broker installed on a Raspberry Pi. I refer to the tinyGSM library and this tutorial along with this example. The ESP32 remains in infinite restart mode. I would like to know if…
Laila Elkaddar
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1 answer

Connect HC-05 and esp8266 with MQTT protocol

I trying to use Bluetooth HC-05 with esp8266 to connect with Mqtt broker (Raspberry Pi), I already know how to connect by Wi-Fi, because there are a lot of example code for it. But not for Bluetooth. Can it possible to use Bluetooth to connect with…
Anime Lover
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1 answer

Relay model for controlling the Air Conditioner power supply

I am trying to control my Air conditioner via MQTT protocol. I just want to make the power on and off. How can I calculate the relay current rating for 1126 Watts of power? Link to AC model:…
atluri bhanu chander
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Is there a common message protocol for sensor data on top of MQTT-SN?

I want to communicate various sensor data in a network of sensors. I found MQTT and MQTT-SN as suitable protocols for that. The latter being better suited for sensor networks with support for sleeping devices, predefined communication, alternatives…
cross
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MQTT subscription issue: The length of my received packet is always 19 characters

This is my first post here so bear with me if I accidentally didn't follow conventional standards here. Here's the issue: I am using a teensy 3.2 and WINC1500 wifi breakout to play around with MQTT protocols. I am currently using the AdaFruit MQTT…
byahya
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Using TINYGSM Client write function for PubSub's client.publish()

I have an application of data logger done on ESP32 where a JSON string is published to the MQTT server(QOS 0) using PubSub Library via TINYGSM. I am attaching a sample of the packet sent to the MQTT…
Jash shah
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Connect Fona3G SIM5320 to cloud over MQTT protocol using GPRS/TCP with stm32

I am seeking assistance in connecting the FONA 3G SIM5320 module to the cloud via TCP connect to establish an MQTT connection. I have successfully connected the module using GPRS connectivity by executing the following AT commands: AT+CGATT=1,…
Amal Guibene
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0
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1 answer

Connect 100 ESP8266 WiFi modules to a master (Raspberry Pi Pico W)

I am looking for the most efficient solution for transferring data from ~100 individual ESP8266 WiFi modules, that have sensors connected to them, to my Raspberry Pi Pico W. This will be used for a watering system for an outdoor garden. Each plant…
drew wood
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Bridge Local Mosquitto MQTT broker installed on RPi with cloud MQTT broker

I was trying creating a bridge between the cloud broker (io.adafruit) and mosquitto broker which runs on my Raspberry Pi. I have successfully tested the local mqtt connection whereas connecting to a cloud broker, I am unable to publish or subscribe…
Rahul S Saksule
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3V3 relay control with ESP-01

I am working on a simple circuit whose goal is to control a high voltage device (e.g. a lamp) thanks to a (3V3) relay module, ESP8266-01 and the MQTT protocol. To power this circuit, I am using a 5V phone charger producing a 3.3V voltage through an…
floflo29
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1 answer

MQTT between ESP32 and Raspberry pi running Mosquitto Broker

I have been trying to connect them but it seems like the MQTT connection is not working. That is the only part that is not, I followed this tutorial (https://www.instructables.com/id/How-to-Use-MQTT-With-the-Raspberry-Pi-and-ESP8266/) on how to…
Ish Montalvo
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MQTT + ESP8266-01 and AVR

I'm working in the IoT field and just got started with the WiFi module ESP8266-01. I know how to use the AT comands and HTTP requests, but I want to use MQTT protocol. I have found this library: https://github.com/tuanpmt/espduino, which seems to be…
Lông Nguyễn
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Access meter readings remotely

I am not an expert on interfaces and communication protocols and I am trying to get data from several meters to read it remotely. The meters have an M-Bus interface to a Data-Logger. The Data-Logger has the following interfaces/protocols: To the…
Karen Semmler
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