IMPLEM'ENTAT'ION OF IEEE 1451.3 COMPLIANT TBIM FOR DISTRIBUTED MULTI-DROP SYSTEM

Abstract

The IEEE 1451 standards define sets of common communication interfaces to standardize the connectivity of transducers to microprocessor, instrumentation systems and networks. This is done by defining different standards that address the various aspects of the development of smart networked transducers. There are eight standards that have been defined so far for the set of standard. The IEEE 1451.0 standard provide a common set of functions and communication protocols to facilitate interoperability between standards as well as the creation of new standards. The IEEE 1451.1 standard defines a common control network information object model for connecting transducers to Network Capable Application Processors (NCAP). The IEEE 1451.2 defines a Smart Transducer Interface Module (STIM) and a Transducer Electronics Data Sheet (TEDS) for. connecting to transducers and. NCAPs. The IEEE 1451.3 defines a Transducer Interface Bus Module (TBIM) that is used for transducers that are physically separated but still need to make the connection to the same NCAP. The IEEE 1451.4 will define a mixed-mode transducer interface module. The IEEE 1451.5 will define a protocol for wireless smart sensors. The IEEE P1451.6 proposed a standard that will use Consolidated Auto Network (CAN) as the communication medium between the NCAP and the transducers. The IEEE P1451.7 recently proposed a standard that will use Radio Frequency Identification (RFID) as the communication medium between the NCAP and the transducers. A prototype of the VHDL model of an IEEE 1451.3 standard compliant TBIM (transducer bus interface module) with four channels has been successfully developed. The implemented four channels are analog sensor channel, digital smart sensor channel and two actuator channels respectively. The individual channel trigger logics, serial communication interface, memory block and channel register block were developed according to the standard and designed through VHDL and successfully implemented on FPGA. Basically the IEEE 1451.3 standard defines a bus interface (HomePNA) for all modules and set of instructions to communicate with them. But here we use RS 485 as distributed multidrop bus. In addition to the interface functions, an iv electronic data sheet(TEDS) is included for sensor identification in order to ease the process of including new sensors in a network.