I'm new MQTT. I'm looking at an example MQTT sketch from the PubSubClient library. It looks like this: void callback(char* topic, byte* payload, unsigned int length) { // handle message arrived } EthernetClient ethClient; PubSubClient client(server, 1883, callback, ethClient); void setup() { …

MQTT library PubSubClient - sending float/int/bool data to topics? char convert - #4 by system - Home Automation

Topic		Replies	Views	Activity
Want to publish numeric value to MQTT but can't work out data type conversion Programming	4	3442	May 5, 2021
PubSubClient (invalid conversion from 'int' to 'const char*' [-fpermissive]) Deutsch	7	1987	May 6, 2021
Getting " invalid conversion" error while trying to test MQTT Programming	8	1439	May 6, 2021
Convert any data type to char to publish via MQTT Programming	17	1789	March 11, 2023
Send data in HEX using PubSubClient MQTT library (ESP8266) Programming	9	2896	May 6, 2021