ISO 20242-3-2011 Industrial automation systems and integration - Service interface for testing applications - Part 3 Virtual device service interface《工业自动化系统和集成.pdf

1、Industrial automation systems and integration Service interface for testing applications Part 3: Virtual device service interface Systmes dautomatisation industrielle et intgration Interface de service pour contrler les applications Partie 3: Interface de service de dispositif virtuel ISO 2011 Refer

2、ence number ISO 20242-3:2011(E) First edition 2011-12-15 ISO 20242-3 INTERNATIONAL STANDARDISO 20242-3:2011(E)COPYRIGHT PROTECTED DOCUMENT ISO 2011 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or me

3、chanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.

4、iso.org Published in Switzerland ii ISO 2011 All rights reservedISO 20242-3:2011(E) ISO 2011 All rights reserved iii Contents Page Foreword . v Introduction .vi 1 Scope 1 2 Normative references . 1 3 Terms and definitions . 1 4 Abbreviated terms . 2 5 Conventions for service definitions and procedur

5、es 2 5.1 General . 2 5.2 Parameters 2 5.3 Service procedures . 3 6 VDSI model 4 6.1 Virtual devices and physical devices . 4 6.2 Structure of VDSI . 4 6.3 Description of VDSI services . 9 7 Operating status of a virtual device .37 7.1 Control VD .37 7.2 Operating states of virtual devices .38 8 Serv

6、ice results .41 8.1 Additional information .41 8.2 Service errors .42 Annex A (informative) Implementation guidelines for VDSI 46 Bibliography .57Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of

7、preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental,

8、 in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main t

9、ask of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attent

10、ion is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 20242-3 was prepared by Technical Committee ISO/TC 184, Automation systems and integration, Subcommitte

11、e SC 5, Interoperability, integration, and architectures for enterprise systems and automation applications. ISO 20242 consists of the following parts, under the general title Industrial automation systems and integration Service interface for testing applications: Part 1: Overview Part 2: Resource

12、management service interface Part 3: Virtual device service interface Part 4: Device capability profile template The following parts are under preparation: Part 5: Application program service interface Part 6: Conformance test methods, criteria and reports ISO 20242-3:2011(E)iv ISO 2011 All rights r

13、eservedIntroduction The motivation for ISO 20242 stems from the desire of international automotive industries and their suppliers to facilitate the integration of automation and measurement devices, and other peripheral components for this purpose, into computer-based applications. ISO 20242 defines

14、 rules for the construction of device drivers and their behaviour in the context of an automation and/or measurement application. The main goal of ISO 20242 is to provide users with: independence from the computer operating system; independence from the device connection technology (device interface

15、/network); independence from device suppliers; the ability to ensure compatibility between device drivers and connected devices, and their behaviour in the context of a given computer platform; independence from the technological device development in the future. ISO 20242 does not necessitate the d

16、evelopment of new device families or the use of special interface technologies (networks). It encapsulates a device and its communication interface to make it compatible with other devices of that kind for a given application. ISO 20242-3:2011(E) ISO 2011 All rights reserved vINTERNATIONAL STANDARD

17、ISO 20242-3:2011(E) Industrial automation systems and integration Service interface for testing applications Part 3: Virtual device service interface 1 Scope This part of ISO 20242 defines a service interface for the communication with virtual devices comprising capabilities of software modules and

18、physical devices, accessed via resource management services as defined in ISO 20242-2. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of

19、 the referenced document (including any amendments) applies. ISO 20242-1, Industrial automation systems and integration Service interface for testing applications Part 1: Overview ISO 20242-2, Industrial automation systems and integration Service interface for testing applications Part 2: Resource m

20、anagement service interface 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 20242-1, ISO 20242-2 and the following apply. 3.1 communication object existing object which may be accessed with a communication function to read or write a value ISO 20242-

21、1:2005, definition 2.3 3.2 device capability description text file containing information about the capabilities of virtual devices in a defined format (i.e. structure, syntax) ISO 20242-1:2005, definition 2.5 3.3 device driver software module providing an ISO 20242-specified interface with service

22、functions to call a platform adapter to access physical devices ISO 20242-2:2010, definition 3.1 3.4 function object instance describing one capability of a virtual device ISO 2011 All rights reserved 13.5 operation instance describing one complete procedure 3.6 platform adapter software module prov

23、iding a resource management service interface as defined in ISO 20242-2, which encapsulates the computer platform, including the operating system, the hardware and its peripherals NOTE Adapted from ISO 20242-2:2010, definition 3.2. 3.7 virtual device representation of one or more physical devices an

24、d/or stand-alone software modules that provide an unambiguous view of the resources of a communication interface 4 Abbreviated terms RMS Resource Management Services RMSI Resource Management Service Interface SAP Service Access Point VD Virtual Device VDS Virtual Device Services VDSI Virtual Device

25、Service Interface 5 Conventions for service definitions and procedures 5.1 General This part of ISO 20242 uses the descriptive conventions given in ISO/IEC 10731. The interface between the user of VDS and the provider of VDS is described by service primitives that convey parameters. Because it is no

26、t in the scope of this part of ISO 20242 to deal with data transmission aspects, only the request and confirm primitives apply for confirmed services. To handle events occurring at the service provider of VDS, indication and response primitives are used. The service model, service primitives and seq

27、uence diagrams are descriptions for an interface and its usage. They do not represent a specification for a software implementation by using a specific programming language. Annex A contains rules for using specific programming languages. 5.2 Parameters Service primitives, used to represent service

28、user/provider interactions (see ISO/IEC 10731), convey parameters that indicate information available in this interaction. This part of ISO 20242 uses a tabular format to describe the component parameters of the VDS primitives. The parameters that apply to each group of VDS primitives are set out in

29、 tables throughout the remainder of this part of ISO 20242. Each table consists of three columns, containing the name of the service parameter, and a column each for those primitives and parameter-transfer directions used by the VDS: the request primitives input parameters (Req) or the indication pr

30、imitives input parameters (Ind), and the confirm primitives output parameters (Cnf) or the response primitives output parameters (Rsp). ISO 20242-3:2011(E)2 ISO 2011 All rights reservedOne parameter (or part of it) is listed in each row of each table. Under the appropriate service primitive columns,

31、 a code is used to specify the type of usage of the parameter on the primitive and parameter direction specified in the column, as follows: M parameter is mandatory for the primitive. I parameter is an implementation option, and may or may not be provided depending on the implementation of the VDS p

32、rovider. C parameter is conditional upon other parameters or upon the environment of the VDS user. S parameter is a selected item. O parameter is optional for the service, its presence depends on the contents of the device capability description in accordance with ISO 20242-4. (blank) parameter is n

33、ever present. 5.3 Service procedures 5.3.1 VDS confirmed services The requesting user submits a request primitive to the VDSI. It is implied that the service access point (SAP) exists. The corresponding service processing entity delivers a confirmation primitive to the user after all necessary inter

34、actions are finished or an error has occurred. 5.3.2 VDS event handling The user creates a SAP at VDSI for handling events. An event is signalled with an indication primitive at this access point. The user of VDSI issues a response primitive after all necessary interactions are finished or an error

35、has occurred (see Figure 1). Figure 1 Handling local events with VDS ISO 20242-3:2011(E) ISO 2011 All rights reserved 36 VDSI model 6.1 Virtual devices and physical devices ISO 20242 virtual devices are defined from the needs of the VDSI user. The application requires functionalities that may be pre

36、sented by one or more physical devices and/or software modules (see Figure 2). The functionalities are grouped in accordance with virtual devices that may belong to the following: a dedicated physical device, a number of physical devices, a part of a physical device, or a software module inside the

37、device driver or inside a platform adapter. Figure 2 Mapping of virtual devices to physical devices and software modules 6.2 Structure of VDSI 6.2.1 General An entity of virtual device services (VDS) contains an access point for services to construct and use virtual devices and provides a virtual de

38、vice service interface (VDSI). Virtual devices contain function objects with operations and communication objects. Figure 3 shows the structure in a UML class diagram. ISO 20242-3:2011(E)4 ISO 2011 All rights reserved Figure 3 UML class diagram of VDSI model 6.2.2 Basic management The services for b

39、asic management open a VDSI for use and to control other services. Table 1 gives an overview of these services. Table 1 Basic management services Service Name for Identification Remarks Attach VDSI Entity VDSI_Attach Opens an entity, which has a VDSI, to use all its services and creates the service

40、access points for event handling (see 5.3.2). Cancel Service VDSI_Cancel Cancels the execution of a selected service. 6.2.3 Virtual device handling A virtual device shall be instantiated before it can be used (see 6.2.6). The class of a virtual device is defined in a device capability description. T

41、he template for the device capability description is defined in ISO 20242-4. The number of instances of a virtual device depends on the requirements of the application and can be limited by physical or software resources. After instantiation of a virtual device, the associated function objects can b

42、e created. Table 2 gives an overview of services to be used with virtual devices. ISO 20242-3:2011(E) ISO 2011 All rights reserved 5Table 2 Virtual device services Service Name for Identification Remarks Initiate Virtual Device VDSI_Initiate Creates an instance of a virtual device and opens it for u

43、sing other services with it. Conclude Virtual Device VDSI_Conclude Concludes a virtual device and removes the instance, if there are no conditions to keep the instance. Abort Virtual Device VDSI_Abort Aborts a virtual device and removes the instance, if there are no conditions to keep the instance.

44、Get Virtual Device Status VDSI_Status Gets the status of a virtual device. Identify Virtual Device VDSI_Identify Gets the version and an indisputable identification for the vendor of this virtual device. 6.2.4 Function object handling Function objects are the capabilities of virtual devices needed b

45、y an application to fulfil its tasks. Examples of function objects are software entities described as classes or measurement channels with specific signal processing and parameters. A function object shall be instantiated before it is active, or can be used. The class of a function object is defined

46、 in the device capability description. The template for the device capability description is defined in ISO 20242-4. The number of instances of a function object depends on the requirements of the application and can be limited by physical or software resources. After instantiation of a function obj

47、ect the associated operations can be used and the associated communication objects can be created. Table 3 gives an overview of services to be used with function objects and their operations. Table 3 Function object services Service Name for Identification Remarks Instantiate Function Object VDSI_Cr

48、eate- FuncObject Creates an instance of a function object and opens it for using other services with it. Remove Function Object VDSI_Delete- FuncObject Removes the instance of a function object, if there are no conditions to keep the instance. Execute Operation VDSI_Execute Starts the execution of a procedure associated with the function