ISO 20242-1:2005

Industrial automation systems and integration - Service interface for testing applications - Part 1: Overview

ISO 20242-1:2005 provides an overview of the particularities of International Standard ISO 20242 and its use in the computer-aided testing environment, the main aim of ISO 20242 being to provide users with: independence from the computer operating system; independence from the device connection technology (device interface/network); independence from device suppliers; the ability to certify device drivers with connected devices and their behaviour in the context of a given computer platform; independence from the technological device development in the future.

Systèmes d'automatisation industrielle et intégration — Interface de service pour contrôler les applications — Partie 1: Vue d'ensemble

General Information

• Status: Published
• Publication Date: 26-Oct-2005
• ICS: 25.040.40 - Industrial process measurement and control
• Technical Committee: ISO/TC 184/SC 5 - Interoperability, integration, and architectures for enterprise systems and automation applications
• Drafting Committee: ISO/TC 184/SC 5/WG 6 - Application service interface
• Current Stage: 9060 - Close of review
• Completion Date: 04-Jun-2030

Overview

ISO 20242-1:2005 is Part 1 (Overview) of the ISO 20242 family - an international standard that defines a service interface for testing applications in industrial automation. It explains the architecture and goals of ISO 20242 for Computer-Aided Testing (CAT) and Computer-Aided Quality (CAQ) environments, focusing on platform- and supplier-independence when integrating measurement and automation devices into test systems.

Key goals highlighted:

• Platform independence (operating system independence)
• Interface independence (device connection/network neutrality)
• Vendor independence (device supplier neutrality)
• Support for device driver certification and long-term device compatibility

Key Topics

ISO 20242-1 describes the core components and concepts used across the ISO 20242 series:

• Platform Adapter (PA) and Resource Management Service Interface (RMSI): encapsulate OS resources and peripheral interfaces so device drivers do not depend on a particular operating system or hardware.
• Device Driver and Virtual Device Service Interface (VDSI): present device capabilities as virtual devices to application programs; the driver handles communication with physical devices.
• Device Capability Description (DCD) and Device Capability Profile Template (DCPT): ASCII text files that describe virtual device structure, functions and behavior for consistent device representation.
• Application Program Service Interface (APSI): interface through which test applications access device drivers via a coordinator.
• Coordinator: manages access, synchronization, real-time aspects and events between application programs and device drivers.
• Communication objects, modules, interfaces and virtual device behavior are defined to standardize interaction patterns.

Applications and Who Uses It

ISO 20242-1 is practical for:

• Test system integrators and CAT/CAQ engineers building automated test stations
• Software developers creating device drivers and testing applications
• Device and measurement equipment manufacturers seeking standardized driver behavior and certification
• QA and standards teams in automotive and manufacturing sectors needing vendor- and platform-neutral device integration
• Vendors of platform adapters, fieldbus cards, and plug-in communication extensions

Typical uses:

• Integrating heterogeneous automation and measurement devices into a unified test application
• Abstracting physical devices into virtual devices for simplified test logic
• Enabling device-driver certification and repeatable conformance testing across platforms

Related Standards

ISO 20242 is a multi-part standard. Other parts (planned or specified in the series) cover:

• Resource management service interface (RMSI) details
• Virtual device service interface (VDSI) specifics
• Device capability profile template (DCPT)
• Application program service interface (APSI) specifications
• Conformance test methods, criteria and reports

Keywords: ISO 20242-1, industrial automation standard, service interface for testing applications, platform adapter, device driver, virtual device, device capability description, Computer-Aided Testing (CAT), device independence.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 20242-1
First edition
2005-10-15
Industrial automation systems and
integration — Service interface for testing
applications —
Part 1:
Overview
Systèmes d'automatisation industrielle et intégration — Interface de
service pour contrôler les applications —
Partie 1: Vue d'ensemble
Reference number
©
ISO 2005
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ii © ISO 2005 – All rights reserved

Contents
1 Scope.1
2    Terms and definitions .1
3    Abbreviations.2
4    Service interface concept.3
4.1 General.3
4.2 Platform adapter .4
4.2.1 Features.4
4.2.2 Device communication aspects.4
4.3 Device driver .5
4.3.1
Features.5
4.3.2 Device communication aspects.5
4.4 Device capability description .5
4.4.1 Features.5
4.4.2
Modules .6
4.4.3 Interfaces.6
4.4.4
Communication objects.7
4.4.5 Behaviour of virtual devices.7
4.5 Coordinator .7
Annex A (informative)   Use case for ISO 20242.9
A.1 Activities of users.9
A.2 Activities of vendors .9
A.3 Further activities.9
Annex B (informative)   State diagram for virtual devices .10
Annex C (informative)   Cascading of device drivers .11

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of 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, 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 task 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.
Attention 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 20242-1 was prepared by Technical Committee ISO/TC 184, Industrial automation systems and
integration, Subcommittee SC 5, Architecture, communications and integration frameworks.
In addition to this part, ISO 20242 is envisaged to consist of several more parts dealing with:
• Resource management service interface;
• Virtual device service interface;
• Device capability profile template;
• Application program service interface;
• Conformance test methods, criteria and reports.

iv © ISO 2005 – All rights reserved

Introduction
The motivation for this International Standard stems from 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. It defines 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/network);
• independence from device suppliers;
• the ability to certify device drivers with connected devices and their behaviour in the context of a given computer
platform;
• independence from the technological device development in the future.
ISO 20242 will not involve the development 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.

INTERNATIONAL STANDARD ISO 20242-1:2005(E)

Industrial automation systems and integration — Service
interface for testing applications —
Part 1:
Overview
1 Scope
This part of ISO 20242 provides an overview of the particularities of this International Standard and its use in the
computer aided testing environment.
2 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
2.1
application program
resource designed to help users perform a specific task
NOTE In this International Standard, an application program does any task necessary to run a computer-aided test station
running, with the special requirement that communication with peripheral devices is done.
2.2
application program service interface
interface to communicate with a coordinator
NOTE This will be specified in another part of ISO 20242.
2.3
communication object
existing object which may be accessed with a communication function to read or write a value
2.4
coordinator
program with a specified interface to handle the access of an application program to one or more device drivers
and to manage real-time application aspects, synchronization and events
2.5
device capability description
text file containing information about the capabilities of virtual devices in a defined format (i.e. structure, syntax)
NOTE This will be specified in another part of ISO 20242.
2.6
device driver
program with an ISO 20242-specified interface containing service functions that call the platform adapter to access
physical devices
2.7
interface
keyword identifying a class for the description of device functions
NOTE A device function inside the device driver is an instance of such an interface.
2.8
interface driver
program handling the data transfer via a peripheral interface
2.9
module
ISO 20242-defined keyword, identifying a class for the description of virtual devices
NOTE A virtual device inside the device driver is an instance of a module.
2.10
platform adapter
program with an ISO 20242-specified interface, encapsulating the computer hardware and its periphery and
providing services to communicate with connected devices and to use other resources of the computer operating
system
2.11
resource management service interface
set of ISO 20242-specified service functions to communicate with a platform adapter
2.12
virtual device
representation of one or more physical devices and/or stand-alone program entities to provide an unambiguous
view on the resources of a communication interface
2.13
virtual device service interface
set of ISO 20242-specified service functions to communicate with a virtual device
NOTE These service functions use the Resource Management Service Interface (platform adapter) to access physical
devices and/or provide the needed capabilities by contained software tasks.

3 Abbreviations
APSI Application Program Service Interface
ASCII American Standard Code for Information Interchange
CAQ Computer Aided Quality Assurance
CAT Computer Aided Testing
CIM Computer Integrated Manufacturing
CORBA Common Object Request Broker Architecture
DCD Device Capability Description
DCPT Device Capability Profile Template
OOP Object-Oriented Programming
PA Platform Adapter
PDU Protocol Data Unit
RMSI Resource Management Service Interface
XML eXtensible Markup Language
VD Virtual Device
VDSI Virtual Device Service Interface
2 © ISO 2005 – All rights reserved

Testing Application Program (CAT)
Device Capability
Application Program Service Interface
Profile Template
Coordinator (Software)
Device
Virtual Device Service Interface
Capability
Description
(File)
Device
Device Device
Driver
Driver Driver
(Software)
(Software) (Software)
Resource Management Service Interface
Platform Adapter (Software)
Virtual Virtual
Computer Operation System
Device Device
Physical Physical Physical Physical
Device Device Device Device
Figure 1 ― Service interfaces defined in ISO 20242
4 Service interface concept
4.1 General
An essential function of an ongoing manufacturing operation is its quality assurance to make sure that high quality
is designed into the product and that the manufacturing operation produces the desired quality. For control of this
quality, test stations are implemented which may be part of the manufacturing process itself or are stand-alone
systems. The computer is an extremely effective tool to control test stations, monitor performance of processes,
collect and evaluate data, and issue quality reports.
The use of computers in test stations is called Computer-Aided Testing (CAT), which falls under the Computer-
Aided Quality Control (CAQ) heading in the Computer Integrated Manufacturing (CIM) terminology. Test stations
use measurement and automation devices to acquire data and to control test scenarios (see Figure 1).
The application programs on computers in CAT communicate with automation and measurement devices via
interfaces. This part of ISO 20242 defines the Application Program Service Interface (APSI) that contains a list of
defined services to access any number of device drivers
...