The Fieldbus Foundation issued a FOUNDATION Wireless and Remote I/O (WIO) preliminary specification to address fieldbus transducer blocks for wired HART and WirelessHART devices, together with updates to the WIO System Architecture and WIO Data Structures related to the transducer block specification.

Part of the FOUNDATION protocol for Remote Operations Management solution implementing wireless and remote I/O, the new technical specification defines a fieldbus transducer block used to represent HART devices within FOUNDATION for Remote Operations Management devices. Both wired HART and WirelessHART devices may be represented in this block. In addition, the specification describes the expected method for HART configuration tools and asset-managing hosts to access HART devices using the native HART command protocol transported through the FOUNDATION High Speed Ethernet (HSE) network. The specification also defines structures to identify and maintain HART device status in wired multi-drop networks, as well as in WirelessHART mesh networks connected to FOUNDATION for Remote Operations Management devices.

“The new transducer block specification will benefit end-users who need to be able to interface HART and WirelessHART devices to FOUNDATION fieldbus to improve their integration with a control system, or with FOUNDATION devices,” said Dave Glanzer, director of technology development. “They may also require a networked method for an asset-managing host to access a large set of HART and WirelessHART devices for HART configuration and maintenance purposes.”

Within the FOUNDATION architecture, H1 and HSE provide a distributed function block capability with HSE serving as a larger pipeline offering increased speed and throughput. The WIO development expands these capabilities by establishing open, non-proprietary specifications for a wired or wireless HSE backhaul network integrating various wireless FOUNDATION for Remote Operations Management devices with interfaces to wireless field device networks.

HSE provides an efficient way to bring large concentrations of discrete and analog field I/O from modular devices back to the control room using a high-speed HSE connection. Employing HSE devices functioning like a smart remote terminal unit (RTU), the technology brings all forms of conventional I/O into the native fieldbus environment easily. This solution makes discrete-in, discrete-out, analog-in, analog-out and H1 fieldbus available over a common Ethernet network. The addition of remote I/O further tightens the integration of process instrumentation within a FOUNDATION control system infrastructure.

Access to FOUNDATION technical specifications is a key benefit of Fieldbus Foundation membership. The specification is available free for review by foundation members, and can be accessed in the Preliminary Specifications area of Fieldbus Forums. During the review cycle, anyone identifying private rights (i.e., patents, copyrights and trademarks) within the specification should contact the Fieldbus Foundation at