MODBUS encapsulated transport interface

• US 7,574,512 B2
• Filed: 04/15/2004
• Issued: 08/11/2009
• Est. Priority Date: 04/15/2004
• Status: Active Grant

• Current Assignee: Schneider Automation Incorporated (Schneider Electric SE)
• Original Assignee: Schneider Automation Incorporated (Schneider Electric SE)
• Inventors: Dube, Dennis Joseph Wilfrid
• Primary Examiner(s): LIN, WEN TAI
• Application Number:
  US10/709,136
• Publication Number:
  US 20050256964A1
• Time in Patent Office: 1,944 Days
• Field of Search: None
• US Class Current: 709/230
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]

Abstract

A method for encapsulating HTTP messages within a MODBUS message is described in the present invention. This MODBUS message can be encoded and sent using either MODBUS/TCP or serial MODBUS. Within MODBUS, the encapsulation is built using the MODBUS Encapsulation Interface (MEI). The HTTP message may contain HTML, XML, XHTML, or SGML.

Claims

1. A method of communicating between an end automation device having a full or emulated HTTP server and a web browser in an Ethernet environment comprising the following computer implemented steps:

sending an HTTP request message from said web browser to a process that encapsulates said request message in a MODBUS type protocol;

transmitting said request message to said automation device;

responding to said request message by said automation device with a reply message using the MODBUS type protocol;

transmitting said reply message to said process;

reformatting said reply message such that the message is understandable by said web browser;

sending the reformatted reply message to said web browser.

2. The method of claim 1 wherein the MODBUS type protocol is the MODBUS/TCP protocol.

3. The method of claim 1 wherein the MODBUS type protocol is the serial MODBUS protocol.

4. The method of claim 1 wherein the request message uses HTTP and HTML.

5. The method of claim 1 wherein the request message uses HTTP and XML.

6. The method of claim 1 wherein the request message uses HTTP and XHTML.

7. The method of claim 1 wherein the request message uses HTTP and SGML.

8. A method of communicating between an end automation device having a full or emulated HTTP server and a personal computer in an Ethernet environment comprising the following computer implemented steps:

sending an HTTP request message from said personal computer to a process that encapsulates said HTTP request message in a MODBUS type protocol;

transmitting said request message to said automation device;

responding to said request message by said automation device with a reply message using the MODBUS type protocol;

transmitting said reply message to said process;

reformatting said reply message such that the message is encoded in HTTP;

sending the reformatted reply message to said personal computer.

9. The method of claim 8 wherein the MODBUS type protocol is the MODBUS/TCP protocol.

10. The method of claim 8 wherein the MODBUS type protocol is the serial MODBUS protocol.

11. The method of claim 8 wherein the HTTP request message uses HTML.

12. The method of claim 8 wherein the HTTP request message uses XML.

13. The method of claim 8 wherein the HTTP request message uses XHTML.

14. The method of claim 8 wherein the HTTP request message uses SGML.