I have MQTT working with one GPIO output on a Nodemcu and can turn the output on an off. I have a second unit with a temperature sensor on the MQTT topic /ESP02/Dallas/Temperature. When I add the following to the configuration file, HA won’t start and no log file is created making debugging somewhat dificult.
sensor:
platform: mqtt
state_topic: "/ESP02/Dallas/Temperature"
name: "ESP02 Temp"
qos: 0
unit_of_measurement: "°C"
value_template: '{{ value.x }}'
Removing that text and rebooting allows HA to start. Any clues?