Smart function block for integration of plcs into a control system and methods for the same

A system 22 for controlling a process in a process plant comprising plural field devices 44, 46, 53 operating to process material in the process plant, a controller 40 sending and receiving signals to and from the field devices effecting control of the process plant, an input/output module 48 between the controller and the field devices, a programmable logic controller 49 disposed between a subset 53 of the field devices and the input/output module and an integration function block instantiated in the controller. The PLC operating to control the subset of the plural field devices and having plural registers associated with each device. The integration function block operable during configuration to receive an assignment of a set of registers of the PLC corresponding to PLC parameters of one of the devices, each register corresponding to a parameter of the device and create an association between the PLC parameter for each register in the set of registers and a corresponding parameter of the controller. The integration function block may be operable, during configuration, to automatically configure itself or the function block may be selected by a user. Receiving an assignment of a set of registers of the PLC may comprise receiving a PLC control tag, the tag associated with a set of register and the integration function block may be operable to reconfigure itself if the registers associated with the tag change.