It is not possible to create an ETS project from an EIB investment without loss. Nevertheless, for the reconstruction of a plant, the support of special software, which searches for all devices of the plant, determines their application, interprets the parameter settings (not always unambiguously) and determines the group address assignments, is a considerable help.
Problem of reconstruction
Reading device data from existing systems and creating ETS projects based on them was a comparatively simple task until the end of the 90s. The EIB devices used at that time often used a bus coupler with a very small memory (BCU1). Interpreting the contents of the memory was easy because there was a fixed description.
For subsequent generations of devices with higher performance, either an additional processor with more memory was coupled to the BCU1, the BCU2 or even the BIM M112 was used. The allocation of the memory of BCU2 / BIM M112 is not fixed, but can be assigned dynamically during the download by the application. The BCU2 / BIM M112 offers manufacturers a much larger memory. This significantly increases the possibilities for controlling the assignment of communication objects (switchable objects) via parameters. However, these parameters are often not loaded into the devices. This means that there are special parameter settings that are made during configuration and have a significant influence on the memory image in the device, but which are only included in the ETS project. After the loss of the project, the memory dump can no longer be interpreted unambiguously because there are usually a very large number of valid combinations for the memory dump.
Devices with an additional processor and memory use the BCU only as a “gateway” to the EIB. These devices are programmed with special software from the manufacturers or special load controls for the ETS. The memory of these devices cannot be read out because it is not known which memory areas are occupied and how they belong together. Thus, an interpretation is out of the question.
Very powerful devices are based, for example, on the BIM M112, which has a comparatively huge memory. Reading through the EIB (9600 baud) could be a very lengthy process. Since, of course, these devices also work with switchable object types and parameter assignments, the interpretation of the almost unlimited variety of combinations can take several years even on a very powerful PC.
A ray of hope thanks to the manufacturer’s interface and new algorithms
The reconstruction problems listed above can only be solved by knowing the relevant memory areas and additional information for interpretation. In order to incorporate this information into the reconstruction process, an interface was agreed with device manufacturers. This interface enables manufacturers to create their own reconstruction functions (as plug-ins) that control the reading and interpretation of their applications. The time required and the bus load can be significantly reduced, as the relevant memory areas are known. However, this information must already be available during readout, i.e. on the PC at the system. In general, for all devices, the interpretation time can be greatly reduced by clever algorithms taking into account probabilities.
Does the reconstruction make any sense at all under these conditions?
Most devices are still equipped with bus couplers that can be read and interpreted by the reconstruction. In older systems, the proportion of devices that can be interpreted is considerably higher. The result of the readout initially provides a very good overview of the devices and applications used in the project. The automatically created project can be analyzed and always used as a secure basis for plant reconstruction. During the reconstruction, the application data of the devices certified by EIBA/Konnex are used. As a result, the effort required to reconstruct an unknown plant is significantly reduced.
Reconstruction is a powerful tool that saves a lot of time and effort in obtaining lost project data.