Eclipse 4diac Logo design once use everywhere Open Source PLC Framework for
Industrial Automation & Control

Documentation

Development - Structured Datatypes

Structured Datatypes

FORTE provides support for structured datatypes STRUCT. Thus the encapsulation of data, which belongs together, is possible and the engineering is facilitated. Currently STRUCT datatypes have to be implemented in FORTE, since there are no export-filters. Based on the Compliance Profile for Feasibility Studies only the unique ASN1-tag of the STRUCT-datatype is used for encoding. Therefore the ASN1-tag has to be set to the same value on all devices that exchange STRUCT-datatypes over the network! For testing and documentation purposes a sample datatype is provided:

Example STRUCT

The definition file TestStruct.dtp is included in 4DIAC-LIB. The according implementation FORTE_TestStruct.cpp and FORTE_TestStruct.h is provided in the module test of FORTE.

Caution: the ASN1-tag provided in the dtp-file has to match the typeID provided in the constructor of the implementation of the datatype.

<ASN1Tag Class="APPLICATION" Number="1" />

leads to

typeID=(e_APPLICATION+e_CONSTRUCTED+1)

Where to go from here?

Go back to Development index:

Development Index

If you want to go back to the Start Here page, we leave you here a fast access

Start Here page

Or Go to top