Software - OPC
Kepware's Modbus OPC Server Suite works in conjunction with KEPServerEX to provide OPC Data Access to Modbus compatible devices and PLCs. The intuitive user interface of KEPServerEX allows users to easily set up reliable Modbus connections. Currently, the suite includes the Modbus Ethernet, Modbus RTU Serial, Modbus RTU Server, Modbus ASCII Serial, and Modbus Plus drivers. Users can employ all of the drivers included in the suite to connect to an unlimited number of compliant devices with a single license.
Modbus, Modbus TCP
Zero-based and one-based addressing; adjustable block reads (1-125); byte order swapping (Modbus or Intel); holding register bit mask writes; "modified" Modbus support for flow computers; dial-up modem support; automatic tag database generation; Ethernet encapsulation for Serial drivers; Modbus TCP framing for RTU Serial; support for Modbus TCP or UDP enabled devices; multi-threaded design; write optimization and error recovery
Please refer to Kepware's website for current specification information: http://www.kepware.com/Products/Modbus_Suite.asp