Try the MatrikonOPC Server for SIMATIC for FREE now. The MatrikonOPC Server for SIMATIC download is shareware that can be distributed freely. It is a fully functioning application that can be used for 30 days after which time it must be licensed.
The MatrikonOPC Interface for SIMATIC is an OPC compliant server that enables data exchange between OPC clients and 505 PLC's. The server provides read and write access to most register types, and supports extended addressing for PLC's with V registers greater than 65535.