Patent ID: 6587884
Filing Date: 2003-07-01
Classification: G05B,H04L

Abstract:
An interface module for receiving data requests from a remote location in order to provide access to a programmable logic controller from a communication network, the module comprising:a central processing unit; a real time operating system operating the central processing unit; a network interface for communicating with the communication network at a nominal data transfer rate of not less than 100 Mbs; a back plane driver for communicating with the programmable logic controller through a back plane of the programmable logic controller; a dual protocol stack comprising: a first protocol stack for communicating a broad range of network messages; a second protocol stack for quickly communicating a specialized set of network messages; a client task for communicating with the back plane driver and the protocol stack for initiating received requests; a server task for communicating with the back plane driver and the protocol stack for responding to received requests; and a protocol task for communicating with the back plane driver and the protocol stack for receiving and responding to protocol task requests.