JP2007241932A - Remote monitoring system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a remote monitoring system with high versatility without necessity for mounting exclusive program etc. in a remote monitoring system which operates data of an electronic equipment by an information processing system connected through a network. <P>SOLUTION: The electronic equipment has a memory storing a Web page file describing access method to the data stored in a memory in the electronic equipment, receives read-out request or write-in request of the Web page file transmitted from a Web browser of an information processing system, analyzes that an access method to the data is described, and returns the access result to the Web browser of the information processing system while accessing to the data. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a remote monitoring system in which parameter settings on a memory provided in an electronic device are performed by an information processing apparatus connected via a network.

  The parameter information of the units constituting the programmable controller (hereinafter referred to as “PLC”) as an electronic device is generally the PLC I / O memory area (input / output relay area, internal auxiliary relay area, special relay area, etc.) ) And data memory areas (data register area, special register area, etc.). A so-called remote monitoring system in which control data and user programs stored in a memory provided in the PLC are operated on a personal computer connected via a network is conventionally known.

  Conventionally, in order to realize this function, (1) a PLC ladder program or the like accesses these memories to read / write data from / to an external user interface. Reading / writing is performed via a manufacturer-provided protocol that is accessed with a simple memory allocation image.

  In recent years, with the advancement of Internet technology, the PLC side becomes a Web server by using Web technology without using dedicated software, and a variable associated with a memory is rewritten from the Web browser via the http protocol, On the other hand, a method of reflecting it in a real memory has been developed (see Patent Document 1).

  In this type of remote monitoring system, it is necessary to store a Web text (HTML file) to be displayed on a Web browser in advance in a memory provided in the PLC in order to mount a Web server function on the PLC. Therefore, in order to change or newly add an HTML file once stored in the memory, it is connected to the PLC using dedicated software, and a predetermined operation for making necessary changes or additions is performed. It was needed.

  In such a remote monitoring system, the process for writing to and reading from a specific memory address differs depending on whether the connection between the PLC and the personal computer is a local connection or a remote connection. It was.

  When the PLC is connected locally, it is necessary to use an editor for displaying and editing, and specific middleware and firmware for accessing the memory. In addition, when the PLC is connected remotely, a specific communication server function and a client-server communication function may be used on the remote device (PLC) in addition to the above-described local memory access function. In addition to the data exchange over the network, processing of each communication driver is added.

  A software block diagram on the client side and server side in the conventional remote monitoring system is shown in FIG. Here, the client side means a client terminal on which a user changes or adds a setting, and a personal computer is usually used. The server side means an electronic device (PLC in this example) that is a target for which a user changes or adds a setting using a client terminal.

  The software on the client side has a hierarchical structure as shown in the figure, where 101 is a Web browser, 102 is XSLT, 103 is SOAP, 104 is http, 105 is TCP / IP, and 106 is Each LAN driver is shown. Similarly, on the server side, reference numeral 107 is a LAN driver, 108 is TCP / IP, 109 is an http, 110 is an html file, 111 is SOAP, 112 is XSLT, 113 is XML, and 114 is a server side program. ing.

The XSLT (XML Stylesheet Language Transformations) 102 and 112 are simple languages for converting a document described in the XML language into another XML document such as XHTML. SOAP (Simple Object Access Protocol) 103 and 111 are protocols for calling up data and services in other computers based on XML, HTTP, and the like.
Japanese Patent Application No. 2004-46618

  In such a conventional remote monitoring system, in order to execute setting of parameters stored in the memory in the PLC that is the target of remote monitoring in the client terminal, a specific editing, communication, and service function is performed by the PLC. Need to be implemented.

  However, since the configuration and communication protocol of each device differ depending on the PLC manufacturer, etc., it is necessary to implement the above editing, communication, and service functions each time to suit each, lacking versatility and labor. The drawback of this was pointed out.

  In addition, there is a problem that the cost increases due to the implementation of these editing, communication, and service functions in the PLC.

  The present invention has been made paying attention to such conventional problems, and an object thereof is to provide an information processing apparatus in which parameter settings on a memory provided in an electronic device are connected via a network. It is an object of the present invention to provide a highly versatile remote monitoring system that does not require the installation of a dedicated program or the like regardless of the manufacturer of the electronic device to be remotely monitored.

  Other objects and effects of the present invention should be easily understood by those skilled in the art by referring to the following description of the specification.

  According to the embodiment of the present invention, an electronic device including an FTP server, a memory, an information processing device, a network connecting the electronic device and the information processing device, and data stored in a memory in the electronic device are A remote monitoring system for accessing on a web browser provided in an information processing apparatus, wherein an electronic device stores a web page file that describes a method for accessing data stored in a memory in the electronic device. A web page file analyzing means for receiving a read request or a write request for a web page file transmitted by FTP from the web browser of the information processing apparatus and analyzing the web page file; Describes how to access data stored in memory And a control unit that controls to access the corresponding data according to the access method and to return the access result to the Web browser of the information processing apparatus by FTP. It is characterized in that data stored in a memory in an electronic device connected via a network is accessed on a browser.

  With such a configuration, editing of data stored in the electronic device is performed using a general Web browser, and a communication function for accessing a remotely located memory uses a standard FTP protocol. This makes it possible to provide a highly versatile remote monitoring system that does not require a dedicated program or the like, regardless of the manufacturer of the target electronic device.

  In addition, when remotely placed, the Web page file is limited to processing such as reading within the electronic device, so that sufficient performance can be achieved even in hardware configurations where the document understanding ability of the electronic device is poor. It becomes. Furthermore, even if the processing capability of the electronic device is high and it has functions such as a Web server, database server, application server, etc., memory access on the electronic device side can be performed directly from the Web browser side, reducing middleware It becomes possible to do.

  According to an embodiment of the present invention, the electronic device is a programmable controller.

  With such a configuration, it is possible to perform operations such as editing control data and user programs stored in the programmable controller on a personal computer as an information processing apparatus connected via a network.

  According to the embodiment of the present invention, a Web page file describing a method for accessing data stored in a memory in an electronic device is described in a parameter EntityReference format based on the DOM specification.

  In the remote monitoring system of the present invention, in the remote monitoring system in which the parameter setting on the memory provided in the electronic device is performed by the information processing apparatus connected via the network, regardless of the manufacturer of the target electronic device, It is possible to provide a highly versatile remote monitoring system that does not require the installation of a dedicated program or the like.

  In the following, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  An overall configuration diagram of a remote monitoring system according to the present invention is shown in FIG. As shown in the figure, the remote monitoring system is roughly configured by a personal computer 1 as an information processing device, a PLC 2 as an example of an electronic device, and an Ethernet (registered trademark) 3 as a network connecting them. Yes. At this time, the PLC 2 becomes the server side, and the personal computer 1 becomes the client side terminal.

  As shown in FIG. 1, the personal computer 1 includes a Web browser 10, a DOM 11, a cookie 12, and an OS (Operating System) 13. The PLC 2 connected to the personal computer 1 via the network 3 includes an ftp server 20, a memory management 21, a memory 22, a file system 23, and a web page file 30.

  Here, DOM11 is an abbreviation for Document Object Model, which treats elements such as characters and images in a Web page as objects, and dynamically changes the Web page by using its attributes and methods. It is the intended technology. The following three functions are realized by using DOM. (1) Dynamic Content: A function for dynamically inserting and deleting characters and images. In addition, you can select and search for character strings. (2) Dynamic Styles: Internet Explorer 4.0 (registered trademark) supports CSS (Cascading Style Sheet), but if this Dynamic Styles function is used, the contents of the style can be changed dynamically. . For example, it is possible to change the color and font size of the character string pointed to by the mouse cursor. (3) Absolute Positioning: A function for displaying an object in a Web page at an arbitrary position on the page. This function can also be used dynamically after the page is displayed.

  The web page file 30 describes a method for accessing setting data stored in a memory (a RAM 27 described later) in the PLC 2. In the present invention, the Web page file 30 is described in a parameter EntityReference format based on the DOM specification.

  In this embodiment, editing uses a general Web browser 10 compliant with the DOM standard, and the communication means for accessing the memory 22 in the remotely located PLC 2 uses the FTP protocol on TCP / IP. To do. By adopting the standard FTP protocol, and remotely arranged PLC, by using the function of the FTP server 20 that is mounted as standard, the necessary web page 30 is stored in the PLC 2. It achieves a predetermined purpose without implementing specific software. Further, as will be described later in detail, the network 3 referred to here differs depending on whether the connection between the personal computer 1 serving as the client terminal and the PLC functioning as the server is a local connection or a remote connection.

  In the above configuration, the web page file 30 is arranged on the server side, in other words, in the PLC 2. However, the web page file 30 can also be stored in the personal computer 1 that is the client side terminal. . FIG. 2 shows a system configuration when the Web page file 30 is arranged on the server device side (PLC2), and FIG. 3 shows a system configuration when the Web page file 30 is arranged on the client terminal side (PC 1). Each figure is shown.

  As shown in FIG. 2, the client terminal (personal computer 1) and the server device (PLC2) are connected to each other via the communication interface 14 (client side), the network 3, and the communication interface 24 (server side). Yes. The PLC 2 stores an MPU 25, a ROM 26, a RAM 27, a RAM 28, a drive interface 29, and a web page file 30. Here, a program for executing a microcomputer is stored in the ROM 26, and setting data such as a PID multiplier and a counter count value, parameters for system configuration, a user program, and the like are stored in the RAM 27 as parameters. Stored. The RAM 28 is a work RAM.

  At this time, when the network 3 is configured by a USB or the like, the arrangement of the personal computer 1 and the PLC 2 is a short distance, and such an arrangement is called a local arrangement. In this case, file access is executed by designating the drive or folder of the Web page file 30 of the PLC 2 on the personal computer 1 side. On the other hand, when the network 3 is configured by Ethernet (registered trademark) or the like and the personal computer 1 and the PLC 2 are connected via an intranet or the Internet, the arrangement of the personal computer 1 and the PLC 2 is a long distance. This arrangement is called remote arrangement. In this case, file access is executed on the personal computer 1 side by specifying the URL of the web page file 30 of the PLC 2.

  Subsequently, FIG. 3 shows a case where the above-described Web page file 30 is stored in the personal computer 1. Since this figure is almost the same as FIG. 2 except that the web page file 30 is stored on the personal computer 1 side, the same reference numerals are given and description thereof is omitted.

  Also in this example, when the personal computer 1 and the PLC 2 are locally arranged, a USB or the like is used as the network 3. Then, in addition to the base URL described in the Web page, access is performed to the RAM 27 that stores the parameter by offsetbyte. On the other hand, when the personal computer 1 and the PLC 2 are remotely arranged, the network 3 is connected via an intranet or the Internet via Ethernet (registered trademark) or the like. Then, in addition to the base URL described in the Web page, access is performed to the RAM 27 that stores the parameter by offsetbyte.

  Next, in FIG. 4 and FIG. 5, software block diagrams of the personal computer 1 and the PLC 2 are shown. FIG. 4 shows an example in which a personal computer 1 as a client terminal and a PLC 2 as a server device are locally arranged, and a USB is used for connection with the PLC 2. FIG. 5 shows an example in which the personal computer 1 and the PLC 2 which are client terminals are remotely arranged, and a LAN is used for connection with the PLC 2.

  As shown in FIG. 4, in the locally arranged example, the client side (PC 1 side) is provided with a Web browser 41, OS 42, IOCS 43, and USB driver 44, and the server side (PLC2 ) Includes a file system 51, a memory management 52, an IOCS 53, and a USB driver 54. Here, the IOCSs 43 and 53 are input / output control systems (input / output control systems), which are software that enters between the OS and hardware and performs basic processing such as hardware control. . This IOCS is equivalent to what is generally called BIOS (Basic Input Output System). In addition, when creating software, it is possible to provide a buffer between the software and hardware by avoiding direct manipulation of the hardware using this IOCS, and if changes are made to the hardware, the IOCS side By responding to the change, the application software can be used as it is without any changes. Thereby, compatibility can be maintained.

  As shown in FIG. 5, in the example of remote placement, the client side (PC 1 side) includes a Web browser 61, OS 62, file system 63, FTP 64, TCP / IP 65, and LAN control driver 66. On the server side (PLC 2), a file system 71, a memory management 72, an FTP 73, a TCP / IP 74, and a LAN control driver 75 are provided.

  Next, in FIG. 6, the general flowchart which shows the process performed by PLC2 is described. In this embodiment, the Web page file described above is stored in the PLC 2 as the server device. As shown in the figure, the hardware and memory are initialized (step 601), and the memory storing the user program is checked (step 602). Subsequently, the configuration recognition of the I / O units constituting the PLC 2 is executed (step 603), and all the I / O units are refreshed (step 604). Subsequently, it is determined whether or not the execution mode of the program is RUN (step 605). If the execution mode is RUN (step 605, YES), initial processing of user program execution is performed (step 606). The program is executed (step 607). After execution of the user program, I / O refresh processing is performed (step 608), and peripheral service processing described in detail later is executed (step 609). On the other hand, if the execution mode is not RUN in step 605 (step 605, NO), the user program is not executed, the process proceeds to step 608, and I / O refresh is executed. When the execution of the I / O refresh process and the peripheral service process is completed (steps 608 and 609), it is determined again whether or not the execution mode is RUN. If the execution mode is RUN (step 610, YES), Returning to step 607, execution processing of the user program is executed, and the subsequent processing is repeated. On the other hand, if the execution mode is not RUN (step 610, NO), the process returns to step 608, the I / O refresh process is executed, and the subsequent processes are repeated.

  The peripheral service processing of the PLC 2 that is the main part of the present invention will be described in detail with reference to FIG. As shown in FIG. 7, this peripheral service process is executed in response to an ftp protocol stack reception process for receiving a command from the user via the personal computer 1 (step 701). Subsequently, the presence / absence of a file R / W request is identified (step 702). If there is no file R / W request, the peripheral service process ends (step 702, NO). Here, the file R / W request is a get / put (RETR / STOR) command transmitted by FTP from the Web browser of the personal computer 1 and is stored in the PLC 2 to read or write a Web page file. It is a request. If there is a file R / W request (step 702, YES), it is subsequently determined whether the MIME Content-Type is message / External-body (step 703).

  If it is determined to be message / External-body (step 703, YES), data is acquired from the reference URI destination of the message body by ftp (step 704), and the path of the designated URI (URN) is determined. Reading / writing is performed on the target resource (file or memory) (step 705). If it is determined that it is not a message / External-body (step 703, NO), the process proceeds directly to step 705, where data is read / written with the addressed external reference destination and the specified address generated and added by the parameter Entity Reference reference expression. Is executed (step 705), and the ftp protocol stack is returned to the personal computer 1 (step 706). The processing performed in steps 705 and 706 is performed by accessing and reading the target data according to the method of accessing the data in the RAM 27 described in the Web page file, and the access result of the personal computer 1 by FTP. It is to reply to the Web browser 10. After these processes, the peripheral service process is completed. The return process of the ftp protocol stack is executed (step 706), and the peripheral service process is completed.

  Next, file request processing on the personal computer 1 side which is a client terminal will be described with reference to FIG. First, the presence / absence of a file R / W request by the user is determined (step 801). If there is no file R / W request, browser display update processing is executed (step 810), and the processing is completed. On the other hand, if there is a file R / W request from the user (step 801, YES), it is then determined whether the file R / W request is a request for a remote file (step 802). At this time, if the request is not related to the remote file (step 802, NO), R / W processing is executed for the requested file (step 804), and then the presence / absence of the Entity Reference format is confirmed (step 805). .

  Returning to step 802, if the file R / W request is a request for a remote file (step 802, YES), the ftp protocol stack transmission / reception process for transmitting the ftp protocol stack described above to the PLC 2 and receiving the return from the PLC 2. Is executed (step 803). Subsequently, the presence / absence of the Entity Reference format is confirmed (step 805). Here, when there is a format of Entity Reference (step 805, YES), it is determined whether or not it is a URI of a proprietary network (proprietary network) (step 806). Proprietary network here means a network constructed by combining only products from a specific manufacturer. When a problem occurs, a quick response can be expected, and the cause can be identified relatively easily. And so on.

  Here, when it is determined that the URI is a proprietary network URI, the URI (ftp: / ...) of the corresponding message entity is specified by MIME / Message-External-body (step 807). . Then, the target URI (ftp: /// ...) of the Entity Reference is designated (step 808), and the send / receive processing of the ftp protocol stack is executed (step 809). Subsequently, browser display update processing is executed, and the file request processing on the PC side is completed.

  Returning to step 806, if it is determined that the URI is not the URI of the proprietary network, the process directly proceeds to step 808 to specify the target URI (ftp: // ...) of the Entity Reference, and the transmission / reception processing of the ftp protocol stack is performed. When executed (step 809), browser display update processing is executed (step 810).

  Returning to step 805, if there is no Entity Reference format (NO in step 805), the process proceeds to step 809, where the transmission / reception processing of the ftp protocol stack is executed. After the transmission / reception processing of the ftp protocol stack is executed, the browser update processing is executed (step 810), and the file request processing on the PC side is completed.

  As described in steps 806 to 808 above, when the target URI (URN) accesses data on the proprietary network of the lower layer of Ethernet (registered trademark), MIME Content-Type = message / External- Specify the body and get the corresponding message on the server side.

  FIG. 9 shows a display screen example of the personal computer 1 in the remote monitoring system to which the present invention is applied. As shown in the figure, the monitor of the personal computer 1 can display and edit PLC2 parameters (in this example, PBL variables). This display screen is configured as a well-known Web page, and the display window 81 and the reference button 82 are used for searching and selecting a target file. By clicking the reference button 82, the reference screen is displayed. Is displayed so that the user can appropriately select the target file. Then, the selected file name is displayed on the display window 81. The display window 83 and the display button 84 are a display window and a button for allowing the user to select a variable to be displayed. By clicking a downward triangle at the right end of the display window 83 in the pull-down format, variable display that can be selected by the user is displayed. In this example, display of all variables is set as a default, and when the display button 84 is clicked in this state, all variables are displayed. A display window 85 and an edit button 86 are a display window and a button for specifying and editing a variable name to be edited. The display window 85 is also in a pull-down format, similar to the display window 83, and lists variable names that can be selected. By selecting a variable name desired by the user from the list and clicking the edit button 86 in a state where the variable name is selected, the variable can be edited.

The following is an example of a Web page description in this embodiment. This description is a description of Java (registered trademark) Script.
<? xmlversion = "1.0" encoding = "Shift_JIS"?>
<! DOCTYPEhtmlPUBLIC "-// W3C // DTDXHTML1.1 // EN""http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns = "http://www.w3.org/1999/xhtml" xml: lang = "en">
<head>
<script language = "JavaScript">
<!-//
function EditParam (num) {
document.open (); // OPEN the page
var data1, data2, data3, data4, adr1, adr2; // Declares variables data1, data2, adr1, adr2
var HTMLstr;
data1 = new String ("0000");
data2 = new String ("0000");
data3 = new String ("0000");
data4 = new String ("0000");
adr1 = new String ("(% x410000;) *");
adr2 = new String ("(% x410000;) *");
adr1.EntityReference = "0000"; // Initialize the reference destination
if (num == 1) {
var cnt = "0";
var now = new Date ();
data1 = new String ("1234"); // Instantiate and assign the string class "1234" to the variable data1
adr1 = new String ("(% x410000;) *"); // Set the address of memory space 0x410000 on the current file
adr1.EntityReference = data1; // Write data “1234” to the above memory space address
data2 = new String ("5678"); // Instantiate and assign the string class "5678" to the variable data2
adr2 = new String ("RMT1 (% x410000;) *"); // NameSpaceURI prefix on the net = Instantiate the address of memory space 0x410000 on RMT1 as a string class and assign it to the variable address
adr2.EntityReference = data2; // Write data “5678” to the above memory space address
HTMLstr = "Write data ..." + "Self note =" + data1 + "" + "NameSpaceURI note =" + data2;
document.form1.disp.value = HTMLstr; // Display read data
}
else if (num == 2) {
cnt = cnt + "0";
data3 = adr1.EntityReference; // Read data from memory space address above
data4 = adr2.EntityReference; // Read data from memory space address above
HTMLstr = "Entity value is ..." + "self-note =" + data3 + "" + "NameSpaceURI note =" + data4 + "" + cnt + now.getSeconds ();
document.form1.disp.value = HTMLstr; // Display read data
}
setTimeout ("EditParam (2)", 500);
return false;
document.close ();
}
//->
</ script>
</ head>
<body onLoad = "EditParam (1)">
<b><p4> Parameter display / edit </ p4></b>
<form name = "form1">
<input name = "disp" style = "" width: 500px; border: outset; border-color: #FFEEEE; background-color: #FFFFEE; color: # 0000FF ">
<br>
<div id = "HTMLstr"/>
</ form>
</ body>
</ html>

  As described above, in the present invention, editing is performed using a general Web browser conforming to the DOM standard, and a communication function for accessing a remotely located memory has a standard communication protocol such as the FTP protocol over TCP / IP. A remote-installed device uses a standard FTP server function to prepare a necessary editing page without installing specific software as long as it has a necessary Web page. Can be realized.

  In addition, when remotely placed, the Web page file is limited to processing such as reading within the remote device, so that sufficient performance can be achieved even in a hardware configuration where the server-side device has poor document understanding. Is possible. Even when the processing capability of the remote device is high and functions such as a Web server, database server, application server, etc., the memory on the remote side can be accessed directly by the operation from the Web browser side, so middleware can be reduced. It becomes possible.

  As is apparent from the above description, according to the present invention, in a remote monitoring system in which parameter settings on a memory provided in an electronic device are performed by an information processing device connected via a network, the target electronic device Regardless of the manufacturer, it is possible to provide a highly versatile remote monitoring system that does not require the installation of a dedicated program or the like.

1 is an overall configuration diagram of a remote monitoring system according to the present invention. It is a block diagram at the time of arrange | positioning a web page file on the server side. It is a block diagram at the time of arrange | positioning a web page file on the client side. It is a software block diagram of local arrangement. It is a software block diagram of remote arrangement. It is a general flowchart which shows the process in the PLC side. It is a flowchart which shows the detail of the periphery service process by the side of PLC. It is a flowchart which shows the file request process by the side of PC. It is an example of a screen which shows edit processing. It is a software block diagram which shows the conventional remote monitoring system.

Explanation of symbols

1 PC
2 PLC
3 Network 10 Web browser 11 DOM
12 Cookie
13 OS
14 Communication interface 20 ftp server 21 MMS
22 memory 23 file system 24 communication interface 25 MPU
26 ROM
27 RAM
28 RAM
29 Drive interface 30 Web page file 41 Web browser 42 OS
43 IOCS
44 USB driver 51 File system 52 Memory management 53 IOCS
54 USB driver 61 Web browser 62 OS
63 File system 64 FTP
65 TCP / IP
66 LAN control driver 71 File system 72 Memory management 73 FTP
74 TCP / IP
75 LAN control driver 101 Web browser 102 XSLT
103 SOAP
104 http
105 TCP / IP
106 LAN driver 107 LAN driver 108 TCP / IP
109 http
110 html file 111 SOAP
112 XSLT
113 XML
114 Server-side program

Claims (3)

An electronic device including an FTP server, a memory, an information processing device, a network connecting the electronic device and the information processing device, and data stored in the memory in the electronic device is displayed on a Web browser provided in the information processing device. A remote monitoring system accessed via
Electronic equipment
A web page file storage memory for storing a web page file describing a method of accessing data stored in a memory in the electronic device;
Web page file analysis means for receiving a read request or write request for a Web page file transmitted by FTP from a Web browser of the information processing apparatus, and analyzing the Web page file;
When it is analyzed that the access method to the data stored in the memory in the electronic device is described, the corresponding data is accessed according to the access method, and the access result is sent to the Web browser of the information processing apparatus by FTP. Control means for controlling to reply,
A remote monitoring system for accessing data stored in a memory in an electronic device connected via a network on a Web browser of an information processing apparatus.   The remote monitoring system according to claim 1, wherein the electronic device is a programmable controller.   3. The remote monitoring system according to claim 1, wherein the Web page file describing a method of accessing data stored in a memory in the electronic device is described in a parameter EntityReference format based on the DOM specification. .

Images