Patent ID: 6014612
Filing Date: 2000-01-11
Classification: G06F

Abstract:
A diagnostic system for use in a process control network having a plurality of devices communicatively linked over a bus, wherein each of the devices is capable of performing a process control function and of communicating on the bus using scheduled periodic communications to thereby implement a process control scheme during regular operation of the process control network, the diagnostic system comprising:a diagnostic signal generator disposed in a first one of the devices that generates a diagnostic control signal;a communicator coupled to the diagnostic signal generator and configured to deliver the diagnostic control signal via the bus to an input of a second one of the devices using the scheduled periodic communications, wherein the second one of the devices is configured to receive a process control signal from a different signal source during regular operation of the process control network; anda signal receiver that receives an output signal developed by another device in response to the diagnostic control signal.