You are here



i-MTT project: Test interface for Linky meters


This project set up test resources for Linky meters and hubs. Strain communications implementing the Linky-specific CPL, EURIDIS2, and TIC protocols as well as modems were purchased from a test equipment supplier; all this was described using MTT.






The strains provide “low-level” functions, i.e. they only implement the bottom layers of the protocols. Furthermore, they are packaged as separate executables which are interfaced using a specific communications mode.

Codra developed an interface with the MTT (subsequently called i-MTT) providing an easy way to use its functions via EDF R&D test equipment. Key MTT functions included:

  • Communications with the MTT: based on TCP sockets. I-MTT sets up and monitors the connection (notably to detect MTT blocking).
  • Exchange sequencing: exchanges between the MTT and i-MTT are performed via simple unitary functions. i-MTT handles the call sequences used to perform a function.
  • Creating and interpreting APDUs: the MTT does not manage the upper layers of the protocols. i-MTT formats and interprets the data section of messages (called APDUs). Interpretation of COSEM APDUs is applied only to exchanges using CPL and EURIDIS2 media, as TIC produces an ASCII streams.
  • Universal interface: interfaces are defined so that the operations carried out using the three communications protocols implemented by MTT (CPL, EURIDIS2, and TIC) are accessible via the same monitoring functions in the interface. i-MTT offers various logging mechanisms with different severity levels.