LOCAL DEVICE AND PROCESS DIAGNOSTICS IN A PROCESS CONTROL NETWORK HAVING DISTRIBUTED CONTROL FUNCTIONS

A field device for use in a process control network having a plurality of devices communicatively coupled by a two-wire, all-digital communication bus includes a connector that connects the field device to the two-wire, all-digital bus to enable all-digital communication over the bus, a memory that stores a diagnostic test routine having a series of device or process diagnostic test instructions, and a controller that performs the device or process diagnostic test instructions stored in the memory to implement a device or process diagnostic test using the field device. A data collection unit within the field device collects diagnostic data generated during the diagnostic test and a communication unit communicates the collected diagnostic data over the bus to a host device for processing. The controller may include a program language interpreter adapted to interpret the diagnostic test instructions which may be provided to the field device from another one of the devices via the bus.