AS3935 Lightning Detector via MQTT https://cmheong.blogspot.com/2020/04/as3935-lightning-detector-next.html
Server side: mosquitto -c /etc/mosquitto/mosquitto.conf
To test relay module: mosquitto_pub -t 'lightning/commands' -m 'modem_on'
To monitor the topics: mosquitto_sub -t 'lightning/messages' mosquitto_sub -t 'lightning/commands'