I bought a water meter, Bmeters GSD8. It also has a Mbus-module to connect to a monitoring system named "RFM-MB1". Nice, but hardware for Mbus is expensive and hard to diy. So lets try to use electronics in another way. On the board inside the RFM-module there is test connectors. The first one is connected to the ground plane. One ic onboard has marking "95010RP". Seems to be a 1 kbit eeprom, M95010-RMN6P.