Multi-protocol field device interface with automatic bus detection

• US 20060282580A1
• Filed: 06/06/2006
• Published: 12/14/2006
• Est. Priority Date: 06/08/2005
• Status: Active Grant

• Current Assignee: Fisher-Rosemount Systems Incorporated (Emerson Electric Company), Rosemount Incorporated (Emerson Electric Company)
• Original Assignee: Fisher-Rosemount Systems Incorporated (Emerson Electric Company)
• Inventors: Borgeson, Dale W., Peluso, Marcos, Harris, Stuart A., Russell, Alden C. III
• Granted Patent: US 8,112,565 B2
• Time in Patent Office: Days
• US Class Current: 710/62
• CPC Class Codes: G05B 2219/25014 Fieldbus general name of bus connected to machines, detectors, actuators
• CPC Class Codes: G05B 2219/25166 USB, firewire, ieee-1394
• CPC Class Codes: G05B 2219/25217 Configure communication protocol, select between several
• CPC Class Codes: G06F 13/387 for adaptation of different data processing systems to different peripheral devices, e.g. protocol converters for incompatible systems, open system

Abstract

A multi-protocol interface for coupling a field device to a general purpose computer is disclosed. The interface includes measurement circuitry to perform a plurality of measurements on a connected process communication loop to determine a process communication loop type. Then, if the interface includes a protocol interface module that matches the detected loop type, the protocol interface module can be engaged. A method for coupling a field device to a general purpose computer is also provided. In one aspect, power from the general purpose computer is used to power the process communication loop, if the interface determines that the loop is not powered.

Claims

1. A multi-protocol interface for coupling a field device to a general purpose computer, the interface comprising:

a connector module configured to couple to the general purpose computer;

a plurality of process communication terminals coupleable to a process communication loop;

a first protocol interface module coupled to the plurality of process communication terminals and configured to communicate in accordance with a first protocol;

a second protocol interface module coupled to the plurality of process communication terminals and configured to communicate in accordance with a second protocol different from the first protocol;

loop measurement circuitry operably coupled to the process communication terminals; and

a microprocessor coupled to the first and second protocol interface modules and coupled to the measurement circuitry, the microprocessor being configured to determine a process communication loop type based at least in part upon a plurality of loop-related measurements made by the measurement circuitry when a process communication loop is coupled to the process communication terminals, and wherein a protocol interface module having a protocol that matches the detected process communication loop type is engaged for communication.

2. The interface of claim 1, wherein the connector module includes a USB connector.

3. The interface of claim 1, wherein the connector module includes a standard serial connector.

4. The interface of claim 1, wherein the connector module includes a parallel connector.

5. The interface of claim 1, wherein the connector module includes a firewire connector.

6. The interface of claim 1, wherein the connector module includes a PCMCIA connector.

7. The interface of claim 1, wherein the connector module includes a PCI connector.

8. The interface of claim 1, wherein the connector module includes a wireless connection.

9. The interface of claim 1, wherein at least one of the loop-related measurements includes voltage across the process communication terminals.

10. The interface of claim 9, wherein at least one of the loop-related measurements includes measurement of loop impedance.

11. The interface of claim 1, wherein the interface is intrinsically safe.

12. The interface of claim 1, wherein the microprocessor determines process communication loop type based at least in part upon a user'"'"'s response to a loop type suggestion provided to the user.

13. A method of coupling a field device to a general purpose computing device using a multi-protocol interface, the method comprising:

detecting a process communication loop coupled to the interface;

performing a plurality of loop-related measurements on the process communication loop to determine a type of the process communication loop; and

automatically engaging a protocol interface module of the interface that matches the detected process communication loop type.

14. The method of claim 13, wherein at least one of the loop-related measurements includes voltage across the process communication loop.

15. The interface of claim 14, wherein at least one of the loop-related measurements includes measurement of loop impedance.

16. The method of claim 13, and further comprising determining if the process communication loop is powered, and selectively providing power to the process communication loop from the general purpose computing device if the process communication loop is not powered.

17. The method of claim 13, wherein at least one of the loop-related measurements includes detecting polarity of the process communication loop connection, and automatically reversing incorrect polarity before automatically engaging the protocol interface module.

18. The method of claim 13, wherein at least one of the loop-related measurements includes detecting polarity of the process communication loop connection, and reporting an error to a user if the detected polarity is incorrect.

19. A multi-protocol interface for coupling a field device to a general purpose computer, the interface comprising:

a connector module configured to couple to the general purpose computer;

a plurality of process communication terminals coupleable to a process communication loop;

a first protocol interface module coupled to the plurality of process communication terminals and configured to communicate in accordance with a first protocol;

a second protocol interface module coupled to the plurality of process communication terminals and configured to communicate in accordance with a second protocol different from the first protocol; and

means for automatically determining process communication loop type and selectively engaging a protocol interface module that matches the process communication loop type.