Connection to Buderus Logamatic 4112 over MQTT to Homeassistant
An ESP8255 collect the data from the Diagnosis Port of the Logamatic 4112 and send the data to MQTT.
Sub-D 15pol. Pin 14 = GND Pin 5 = RxD
ESP8255: Wire Bridge from Reset to D0 D7 ESP to Pin 5 SubD