1、September 2008DEUTSCHE NORM DKE Deutsche Kommission Elektrotechnik Elektronik Informationstechnik im DIN und VDEPreisgruppe 35DIN Deutsches Institut fr Normung e.V. Jede Art der Vervielfltigung, auch auszugsweise, nur mit Genehmigung des DIN Deutsches Institut fr Normung e.V., Berlin, gestattet.ICS
2、35.100.70; 35.160!$O a synonym for an operational service which is provided by the server ASE and invoked by a client 3.6.45 network a set of nodes connected by some type of communication medium, including any intervening repeaters, bridges, routers and lower-layer gateways B55EB1B3E14C22109E918E8EA
3、43EDB30F09CC7B7EF8DD9NormCD - Stand 2009-03 DIN EN 61158-5-8:2008-09 EN 61158-5-8:2008 13 3.6.46 object abstract representation of a particular component within a device, usually a collection of related data (in the form of variables) and methods (procedures) for operating on that data that have cle
4、arly defined interface and behaviour 3.6.47 object specific service service unique to the object class which defines it 3.6.48 peer role of an AR endpoint in which it is capable of acting as both client and server 3.6.49 point-to-point connection connection that exists between exactly two applicatio
5、n objects 3.6.50 pre-defined AR endpoint AR endpoint that is defined locally within a device without use of the create service NOTE Pre-defined ARs that are not pre-established are established before being used 3.6.51 pre-established AR endpoint AR endpoint that is placed in an established state dur
6、ing configuration of the AEs that control its endpoints 3.6.52 property descriptive information about an object 3.6.53 provider source of a data connection 3.6.54 publisher role of an AR endpoint that transmits APDUs onto the fieldbus for consumption by one or more subscribers NOTE A publisher may n
7、ot be aware of the identity or the number of subscribers and it may publish its APDUs using a dedicated AR. 3.6.55 push publisher type of publisher that publishes an object in an unconfirmed service request APDU 3.6.56 push subscriber type of subscriber that recognizes received unconfirmed service r
8、equest APDUs as published object data 3.6.57 resource a processing or information capability of a subsystem B55EB1B3E14C22109E918E8EA43EDB30F09CC7B7EF8DD9NormCD - Stand 2009-03 DIN EN 61158-5-8:2008-09 EN 61158-5-8:2008 14 3.6.58 server a) role of an AREP in which it returns a confirmed service resp
9、onse APDU to the client that initiated the request b) object which provides services to another (client) object 3.6.59 service operation or function than an object and/or object class performs upon request from another object and/or object class 3.6.60 subscriber role of an AREP in which it receives
10、 APDUs produced by a publisher B55EB1B3E14C22109E918E8EA43EDB30F09CC7B7EF8DD9NormCD - Stand 2009-03 DIN EN 61158-5-8:2008-09 EN 61158-5-8:2008 15 3.7 Abbreviations and symbols AE Application entity AL Application layer ALME Application layer management entity ALP Application layer protocol APO Appli
11、cation object AP Application process APDU Application protocol data unit API Application process identifier AR Application relationship AREP Application relationship endpoint ASE Application service element CIM Computer integrated manufacturing Cnf Confirmation CR Communication relationship CREP Com
12、munication relationship endpoint DL- (as a prefix) Data-link- DLC Data-link connection DLCEP Data-link connection endpoint DLL Data-link layer DLM Data-link-management DLSAP Data-link service access point FAL Fieldbus application layer FIFO First in first out ID Identifier Ind Indication LME Layer m
13、anagement entity OSI Open Systems Interconnect PDU Protocol data unit Req Request Rsp Response SAP Service access point 3.8 Conventions 3.8.1 Overview The FAL is defined as a set of object-oriented ASEs. Each ASE is specified in a separate subclause. Each ASE specification is composed of two parts,
14、its class specification, and its service specification. The class specification defines the attributes of the class. The attributes are accessible from instances of the class using the Object Management ASE services specified in Clause 5 of this standard. The service specification defines the servic
15、es that are provided by the ASE. B55EB1B3E14C22109E918E8EA43EDB30F09CC7B7EF8DD9NormCD - Stand 2009-03 DIN EN 61158-5-8:2008-09 EN 61158-5-8:2008 16 3.8.2 General conventions This standard uses the descriptive conventions given in ISO/IEC 10731. 3.8.3 Conventions for class definitions Class definitio
16、ns are described using templates. Each template consists of a list of attributes for the class. The general form of the template is shown below: FAL ASE: ASE Name CLASS: Class Name CLASS ID: # PARENT CLASS: Parent Class Name ATTRIBUTES: 1 (o) Key Attribute: numeric identifier 2 (o) Key Attribute: na
17、me 3 (m) Attribute: attribute name(values) 4 (m) Attribute: attribute name(values) 4.1 (s) Attribute: attribute name(values) 4.2 (s) Attribute: attribute name(values) 4.3 (s) Attribute: attribute name(values) 5. (c) Constraint: constraint expression 5.1 (m) Attribute: attribute name(values) 5.2 (o)
18、Attribute: attribute name(values) 6 (m) Attribute: attribute name(values) 6.1 (s) Attribute: attribute name(values) 6.2 (s) Attribute: attribute name(values) SERVICES: 1 (o) OpsService: service name 2. (c) Constraint: constraint expression 2.1 (o) OpsService: service name 3 (m) MgtService: service n
19、ame (1) The “FAL ASE:“ entry is the name of the FAL ASE that provides the services for the class being specified. (2) The “CLASS:“ entry is the name of the class being specified. All objects defined using this template will be an instance of this class. The class may be specified by this standard, o
20、r by a user of this standard. (3) The “CLASS ID:“ entry is a number that identifies the class being specified. This number is unique within the FAL ASE that will provide the services for this class. When qualified by the identity of its FAL ASE, it unambiguously identifies the class within the scope
21、 of the FAL. The value “NULL“ indicates that the class cannot be instantiated. Class IDs between 1 and 255 are reserved by this standard to identify standardized classes. They have been assigned to maintain compatibility with existing national standards. CLASS IDs between 256 and 2048 are allocated
22、for identifying user defined classes. (4) The “PARENT CLASS:“ entry is the name of the parent class for the class being specified. All attributes defined for the parent class and inherited by it are inherited for the class being defined, and therefore do not have to be redefined in the template for
23、this class. NOTE The parent-class “TOP“ indicates that the class being defined is an initial class definition. The parent class TOP is used as a starting point from which all other classes are defined. The use of TOP is reserved for classes defined by this standard. B55EB1B3E14C22109E918E8EA43EDB30F
24、09CC7B7EF8DD9NormCD - Stand 2009-03 DIN EN 61158-5-8:2008-09 EN 61158-5-8:2008 17 (5) The “ATTRIBUTES“ label indicate that the following entries are attributes defined for the class. a) Each of the attribute entries contains a line number in column 1, a mandatory (m) / optional (o) / conditional (c)
25、 / selector (s) indicator in column 2, an attribute type label in column 3, a name or a conditional expression in column 4, and optionally a list of enumerated values in column 5. In the column following the list of values, the default value for the attribute may be specified. b) Objects are normall
26、y identified by a numeric identifier or by an object name, or by both. In the class templates, these key attributes are defined under the key attribute. c) The line number defines the sequence and the level of nesting of the line. Each nesting level is identified by period. Nesting is used to specif
27、y i) fields of a structured attribute (4.1, 4.2, 4.3), ii) attributes conditional on a constraint statement (5). Attributes may be mandatory (5.1) or optional (5.2) if the constraint is true. Not all optional attributes require constraint statements as does the attribute defined in (5.2). iii) the s
28、election fields of a choice type attribute (6.1 and 6.2). (6) The “SERVICES“ label indicates that the following entries are services defined for the class. a) An (m) in column 2 indicates that the service is mandatory for the class, while an (o) indicates that it is optional. A (c) in this column in
29、dicates that the service is conditional. When all services defined for a class are defined as optional, at least one has to be selected when an instance of the class is defined. b) The label “OpsService“ designates an operational service (1). c) The label “MgtService“ designates an management servic
30、e (2). d) The line number defines the sequence and the level of nesting of the line. Each nesting level is identified by period. Nesting within the list of services is used to specify services conditional on a constraint statement. 3.8.4 Conventions for service definitions 3.8.4.1 General The servic
31、e model, service primitives, and time-sequence diagrams used are entirely abstract descriptions; they do not represent a specification for implementation. 3.8.4.2 Service parameters Service primitives are used to represent service user/service provider interactions (ISO/IEC 10731). They convey param
32、eters which indicate information available in the user/provider interaction. In any particular interface, not all parameters need be explicitly stated. B55EB1B3E14C22109E918E8EA43EDB30F09CC7B7EF8DD9NormCD - Stand 2009-03 DIN EN 61158-5-8:2008-09 EN 61158-5-8:2008 18 The service specifications of thi
33、s standard uses a tabular format to describe the component parameters of the ASE service primitives. The parameters which apply to each group of service primitives are set out in tables. Each table consists of up to five columns for the 1) parameter name, 2) request primitive, 3) indication primitiv
34、e, 4) response primitive, and 5) confirm primitive. One parameter (or component of it) is listed in each row of each table. Under the appropriate service primitive columns, a code is used to specify the type of usage of the parameter on the primitive specified in the column: M parameter is mandatory
35、 for the primitive U parameter is a User option, and may or may not be provided depending on dynamic usage of the service user. When not provided, a default value for the parameter is assumed. C parameter is conditional upon other parameters or upon the environment of the service user. (blank) param
36、eter is never present. S parameter is a selected item. Some entries are further qualified by items in brackets. These may be a) a parameter-specific constraint: “(=)” indicates that the parameter is semantically equivalent to the parameter in the service primitive to its immediate left in the table.
37、 b) an indication that some note applies to the entry: “(n)” indicates that the following note “n“ contains additional information pertaining to the parameter and its use. 3.8.4.3 Service procedures The procedures are defined in terms of the interactions between application entities through the exch
38、ange of fieldbus Application Protocol Data Units, and the interactions between an application layer service provider and an application layer service user in the same system through the invocation of application layer service primitives. These procedures are applicable to instances of communication
39、between systems which support time-constrained communications services within the fieldbus Application Layer. B55EB1B3E14C22109E918E8EA43EDB30F09CC7B7EF8DD9NormCD - Stand 2009-03 DIN EN 61158-5-8:2008-09 EN 61158-5-8:2008 19 4 Concepts 4.1 Overview This subclause describes fundamentals of the FAL. D
40、etailed descriptive information about each of the FAL ASEs can be found in the “Overview” subclause of each of the Communication Model specifications. 4.2 Architectural relationships 4.2.1 Relationship to the Application Layer of the OSI basic reference model The functions of the FAL have been descr
41、ibed according to OSI layering principles. However, its architectural relationship to the lower layers is different, as shown in Figure 1. - The FAL includes OSI functions together with extensions to cover time-critical requirements. The OSI Application Layer Structure standard (ISO/IEC 9545) was us
42、ed as a basis for specifying the FAL. - The FAL directly uses the services of the underlying layer. The underlying layer may be the data link layer or any layer in between. When using the underlying layer, the FAL may provide functions normally associated with the OSI Middle Layers for proper mappin
43、g onto the underlying layer. OSI MiddleLayersOSI Application Layer OSI Physical Layer OSI Data Link LayerOSI APPhysical Medium Fieldbus Application Layer Physical Layer Data Link Layer FAL User Physical Medium Figure 1 Relationship to the OSI basic reference model 4.2.2 Relationships to other fieldb
44、us entities 4.2.2.1 General The Type 8 Fieldbus Application Layer (FAL) architectural relationships, as illustrated in Figure 2, have been designed to support the interoperability needs of time-critical systems distributed within the fieldbus environment. Within this environment, the FAL provides co
45、mmunications services to time-critical and non-time-critical applications located in Type 8 devices. In addition, the FAL directly uses the data-link layer to transfer its application layer protocol data units. It does this using a set of data transfer services and a set of supporting services used to control the operational aspects of the data-link layer. B55EB1B3E14C22109E918E8EA43EDB30F09CC7B7EF8DD9NormCD - Stand 2009-03 DIN EN 61158-5-8:2008-09 EN 61158-5-8:2008 20 Type 8 FAL User Type 8 Fieldbus Appl
