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A configuration database includes multiple databases distributed at a plurality of physical locations within a process control system. Each of the databases may be accessed by users at any of the sites within the process control system. A database server having a shared cache accesses a database in

A configuration database includes multiple databases distributed at a plurality of physical locations within a process control system. Each of the databases may be accessed by users at any of the sites within the process control system. A database server having a shared cache accesses a database in a manner that enables multiple subscribers to read configuration data from the database with only a minimal number of reads to the database. To prevent the configuration data being viewed by subscribers within the process control system from becoming stale, the database server automatically detects changes to an item within the configuration database and sends notifications of changes made to the item the each of the subscribers of that item so that a user always views the state of the configuration as it actually exists within the configuration database.

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A configuration database includes multiple databases distributed at a plurality of physical locations within a process control system. Each of the databases may be accessed by users at any of the sites within the process control system. A database server having a shared cache accesses a database in

A configuration database includes multiple databases distributed at a plurality of physical locations within a process control system. Each of the databases may be accessed by users at any of the sites within the process control system. A database server having a shared cache accesses a database in a manner that enables multiple subscribers to read configuration data from the database with only a minimal number of reads to the database. To prevent the configuration data being viewed by subscribers within the process control system from becoming stale, the database server automatically detects changes to an item within the configuration database and sends notifications of changes made to the item the each of the subscribers of that item so that a user always views the state of the configuration as it actually exists within the configuration database. for the distributed diagnosis of a physical system includes serveral local diagnostic subsystems that generate local diagnoses based on observations of a component of the physical system. An interface is defined by which the local diagnostic subsystems communicate. Further, an algorithm for assembling a global diagnosis from the local diagnoses is fined. g one of pressure, acceleration, force and torque, an electronic circuit having at least one multiplexer with addressable inputs connected to the sense elements outputs, the at least one multiplexer having an output connected to a signal conditioning circuit path, the signal conditioning circuit path having conditioning components, nonvolatile memory for storing calibration and characterization data for each of the sense elements and the electronic circuit and a data port for transmitting data from the nonvolatile memory to the multiplexers and to the signal conditioning components for each sense element addressed for conditioning the signals for each sense element and to an external controller to enable the external controller to perform mathematical corrections of the conditioned signal. 2. A condition responsive sensor system according to claim 1 in which the sense elements each comprises a bridge network, each bridge network having a bridge voltage node, a ground node, a plus output node and a minus output node and further comprising an electronically programmable resistor connected in series between a voltage source and each respective bridge voltage node for providing a selected bias to each respective sense node. 3. A condition responsive sense element system according to claim 1 further comprising first and second non-condition responsive test bridge networks formed in the electronic circuit, the test bridge networks each having a bridge voltage node, a ground node, a plus output node and a minus output node, the output nodes connected through a multiplexer to the signal conditioning circuit path, the plus and minus outputs of the first test bridge providing signals of a first value, the plus and minus outputs of the second test bridge providing signals of a second value, the test bridge network providing data for diagnosing electronic circuit faults. 4. A condition responsive sense element system according to claim 1 in which the electronic circuit is an ASIC. 5. A condition responsive sense element system according to claim 1 further comprising a sense element diagnostic circuit path including a summing circuit and conditioning components, the plus and minus outputs of an addressed sense element being connected to the summing circuit and being summed with the summed value fed to the conditioning components of the sense element diagnostic circuit path to provide a diagnostic signal, the stored calibration and characterization data for each of the sense elements and diagnostic circuit path transmitted to the external controller for enabling the external controller to perform mathematical corrections of the diagnostic signal. 6. A condition responsive sense element system according to claim 5 further comprising first and second non-condition responsive sense element test bridge networks formed in the electronic circuit, the test bridge networks each having a bridge voltage node, a ground node, a plus output node and a minus output node, the output nodes connected to the diagnostic circuit path through a multiplexer, the plus and minus outputs of the first test bridge network providing signals of a first value, the plus and minus outputs of the second test bridge network providing signals of a second value, the test bridge networks providing data for diagnosing diagnostic circuit path faults. 7. A condition responsive sense element system according to claim 2 further comprising first and second non-condition responsive sense element test bridge networks formed in the electronic circuit, the test bridge networks each having a bridge voltage node, a ground node, a plus output node and a minus output node, the test bridge networks enabling the diagnoses of sense element bias faults. 8. A condition responsive sense element system according to claim 1 in which the condition being sensed is pressure. 9. A condition responsive sense element system comprising a plurality of condition responsive sense elements providing a v oltage output dependent on the condition, the condition being sensed being one of pressure, acceleration force and torque, the sense elements each having a bridge network with a bridge voltage node, a ground node, a plus output node and a minus output node, a voltage source, each bridge voltage node connected to the voltage source, an electronic circuit having first, second and third multiplexers, each having an output and a plurality of address input positions, the plus node of each sense element connected to a respective multiplexer address position of the first multiplexer, the minus node of each sense element connected to a respective multiplexer address position of the second multiplexer and the ground node of each sense element connected to a respective address position of the third multiplexer, a respective register connected to each multiplexer, a signal ground, the output of the third multiplexer connected to a signal ground, a signal conditioning circuit path, the signal conditioning circuit path comprising a differential amplifier having a plus and a minus input and an output, the output of the first multiplexer connected to the plus input of the differential amplifier, the output of the second multiplexer connected to the minus input of the differential amplifier, an offset correction network having a summing circuit with an output and inputs, the input connected to the output of the differential amplifier and an offset circuit controlled by a register to provide a correction proportional to bridge voltage, and a gain correction network having a variable gain amplifier having an input connected to the output of the offset correction network and controlled by a gain correction register, a digital port, an analog to digital converter having an input and an output, the output of the gain correction network inputted to the analog to digital converter to provide a digital signal corresponding to the sensed condition to the digital port, a logic control and a nonvolatile memory section, the nonvolatile memory section being connected to the several registers under the control of the logic control, the digital port forming an interface for transmitting data to and receiving data from an external controller, the nonvolatile memory providing data to the external controller enabling the external controller to perform mathematical error correction for the condition sensor signals and the logic control providing commands for obtaining sense element data from a selected sense element. 10. A condition responsive sense element system according to claim 9 further comprising an electronically programmable resistor connected in series between the voltage source and each respective bridge voltage node for providing a selected bias to each respective sense element when selected and a register for receiving data from nonvolatile memory connected to the electronically programmable resistor to control the value of the resistor. 11. A condition responsive sense element system according to claim 9 in which the condition is pressure. 12. A condition responsive sense element system according to claim 9 further comprising first and second non-condition responsive test bridge networks formed in the electronic circuit, each test bridge network having a bridge voltage node, a ground node, a plus output node and a minus output node, the output nodes and the ground nodes connected respectively to the signal conditioning circuit path and a signal ground through a multiplexer, the plus and the minus output nodes of the first test bridge network providing signals of a first value, the plus and minus output nodes of the second test bridge network providing signals of a second value, the test bridge networks providing data for diagnosing electronic circuit faults. 13. A condition responsive sense element system according to claim 10 further comprising first and second non-condition responsive test bridge networks formed in the electronic circu it, each test bridge network having a bridge voltage node, a ground node, a plus output node and a minus output node, the test bridge networks enabling the diagnoses of sense element bias faults. 14. A condition responsive sense element system according to claim 9 in which the electronic circuit is an ASIC. 15. A condition responsive sense element system according to claim 9 further comprising a sense element diagnostic circuit path including a summing circuit and conditioning components, the plus and minus outputs of an addressed sense element being connected to the summing circuit and being summed with the summed value fed to the conditioning components of the sense element diagnostic circuit path to provide a diagnostic signal, the stored calibration and characterization data for each of the sense elements and diagnostic circuit path transmitted to the external controller for enabling the external controller to perform mathematical corrections of the diagnostic signal. 16. A condition responsive sense element system according to claim 15 further comprising first and second non-condition responsive sense element test bridge networks formed in the electronic circuit, the test bridge networks each having a bridge voltage node, a ground node, a plus output node and a minus output node, the output nodes connected respectively to the diagnostic circuit path and a signal ground through a multiplexer, the plus and minus outputs of the first test bridge network providing signals of a first value, the plus and minus outputs of the second test bridge network providing signals of a second value, the test bridge networks providing data for diagnosing diagnostic circuit path faults. 17. In a condition responsive sensing system having a plurality of condition sense bridge elements, the method comprising the steps of providing a bias for each sense element, providing an electronic circuit having multiplexers, a signal conditioning circuit path having signal conditioning components, an analog to digital converter, logic control, nonvolatile memory and a digital port for transmitting and receiving data, forming the electronic circuit as an ASIC, obtaining electronic calibration data for each sense element during manufacture of the system and storing that information in nonvolatile memory, connecting the electronic controller to an external controller, transmitting data from nonvolatile memory to enable the external controller to perform mathematical corrections to a conditioned digital signal, selecting an address of the multiplexers for connecting outputs of a selected bridge sense element to the signal conditioning circuit path and to transmit basic offset and gain calibration data to send conditioning components in the signal conditioning path, partially conditioning the addressed sense element using the basic offset and gain calibration data transmitted from nonvolatile memory, to provide a partially conditioned signal, converting the partially conditioned signal from an analog format to a digital format in the analog to digital converter to provide a digital signal, transmitting the digital signal to the external controller and completing the conditioning of the partially conditioned signal by performing mathematical corrections to the digital signal in the external controller using the data transferred from the nonvolatile memory. 18. In the method according to claim 17, the additional steps of forming a first non-condition responsive test bridge in the electronic circuit, the first bridge providing a first reference value, forming a second non-condition responsive test bridge in the electronic circuit, the second bridge providing a second reference value, the data from the first and second test bridges providing reference data for diagnostic use of electronic circuit faults. 19. In a condition responsive sensing system having a plurality of condition sense bridge elements, the method comprising the steps of prov