LIAN 98 Protocol Interface for User Applications


The program LIAN 98 offers an interface between the link and the application layer for user applications to send and receive process telegrams. This interface is realized as ring buffer file in control and also in monitoring direction.

While LIAN 98 handles the data traffic with the substations independent, all process telegrams in monitoring direction ( messages, measurands, .. ) are written in a ring buffer file ( RDBfile ) for further processing. Other application programs can use this interface in the same way and read out the process telegrams from the stations for further treatment. In control direction also a ring buffer file ( SDBfile ) is available for the process telegrams to the substation. The application program can write into this ring buffer file process telegrams ( commands, general interrogation, .. ), that are read out and sent to the substation by LIAN 98.

With this interface in LIAN 98 testing of a control system is already possible, even if the specific process communication is not yet available. The software-technical connection of the application program to LIAN 98 takes only very little time. The necessary moduls to write into the ring buffer file and read out of the ring buffer file can be made available from us as source code with structure descriptions. This interface is available in LIAN 98 for master and also for slave simulation.


Program Code for the Process Interface written in C++ for Microsoft Visual Studio 2003


In the LIAN 98 Software master and slave simulation are implemented for the particular protocols. Thereby LIAN 98 handles independently the complete link layer. It is an advantage, to implement existing and tested program parts for the process interface from the LIAN 98 software into a SCADA software and not re-program again. Therefore we offer for SCADA developers to purchase protocol-specific software modules which process the link layer of a master. All with simulation implemented protocols in LIAN 98 are available. All necessary modules for the link layer of a master or slave will be supplied, as "C++ Source Code for Microsoft Visual Studio 2003" with an interface from and to the application layer.


For further information, please contact us.