Playing with MQTT and my SONOFF Basic, with TASMOTA firmware on board, I found a small mistake in the exchanged messages. In a few words, when I sent a MQTT message to power on or off the SONOFF (tasmota/garden/light/sonoffbasic01/cmnd/POWER ON), the device replied to me with the standard topic (stat/sonoffbasic01/RESULT) and not with the "fulltopic".
I immediately thought that the reason was a bug in the firmware and so I opened an "issue"on the GitHub page of TASMOTA.
In a few hours I found the solution, caused by a configuration error and not by a bug of the firmware.
In particular, I left the default value for "MqttClient" parameter, which assumed the same value as "Topic" parameter. For TASMOTA this is not OK. So I changed "MqttClient" parameter with a different value than "Topic" parameter and set mqtt-sonoffbasic01. Please, remember that this parameter must be unique in the entire system.
This is the link to the discussion:
I must admit that in a few hours I found the solution to my problem, thanks to the big support of developer.
Theo Arends, THANK YOU VERY MUCH