Web interface to a programmable controller

An interface module for allowing access to a programmable logic controller system from a communication network at a remote location, the interface module adapted for installation in a slot coupled through a back plane to a programmable logic controller, the module comprising:

• A. a microprocessor;
• B. a real time operating system;
• C. a network interface for coupling the interface module to said communications network;
• D. a back plane driver for coupling the interface module to said back plane and for transferring data between the interface module and said programmable logic controller;
• E. a server application for processing data requests received from said communications network;
• F. a client application for initiating requests received from said communications network;
• G. a protocol stack to enable data transfer between the remote location and said programmable logic controller system;
• and
• H. a server task for interfacing said protocol task with said back plane, said server task for receiving a data request from said protocol stack, accessing said programmable logic controller system for said requested data, and for sending a response to said remote location through said protocol stack and network interface, said response in a framework supplied by said operating system.