1、BRITISH STANDARD BS ISO 17356-4:2005 Road vehicles Open interface for embedded automotive applications Part 4: OSEK/VDX Communication (COM) ICS 43.040.15 BS ISO 17356-4:2005 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 12 January 2006 BSI
2、12 January 2006 ISBN 0 580 46883 6 National foreword This British Standard reproduces verbatim ISO 17356-4:2005 and implements it as the UK national standard. The UK participation in its preparation was entrusted to Technical Committee AUE/16, Electrical and electronic equipment, which has the respo
3、nsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK. A list
4、of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Corresponde
5、nce Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of its
6、elf confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii to vii, a blank page, pages 1 to 55 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issue
7、d. Amendments issued since publication Amd. No. Date Comments Reference number ISO 17356-4:2005(E)INTERNATIONAL STANDARD ISO 17356-4 First edition 2005-11-01 Road vehicles Open interface for embedded automotive applications Part 4: OSEK/VDX Communication (COM) Vhicules routiers Interface ouverte pou
8、r applications automobiles embarques Partie 4: Communications (COM) OSEK/VDX BS ISO 17356-4:2005ii BS ISO 17356-4:2005iii Contents Page Foreword iv Introduction v 1 Scope . 1 2 Normative references . 1 3 Interaction Layer . 1 3.1 Overview 1 3.2 Message reception 4 3.3 Message transmission . 7 3.4 By
9、te order conversion and message interpretation . 14 3.5 Deadline monitoring . 16 3.6 Notification 21 3.7 Communication system management 22 3.8 Functional model of the Interaction Layer . 26 3.9 Interfaces . 28 4 Minimum requirements of lower communication layers 43 5 Conformance Classes 44 Annex A
10、(informative) Use of ISO 17356-4 (COM) with an OS not conforming to ISO 17356-3 46 Annex B (informative) Application notes . 47 Annex C (informative) Callouts . 54 BS ISO 17356-4:2005 iv Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards
11、 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 organiza
12、tions, 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 t
13、he 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
14、 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 17356-4 was prepared by Technical Committee ISO/TC 22, Road ve
15、hicles, Subcommittee SC 3, Electrical and electronic equipment. ISO 17356 consists of the following parts, under the general title Road vehicles Open interface for embedded automotive applications: Part 1: General structure and terms, definitions and abbreviated terms Part 2: OSEK/VDX specifications
16、 for binding OS, COM and NM Part 3: OSEK/VDX Operating System (OS) Part 4: OSEK/VDX Communication (COM) Part 5: OSEK/VDX Network Management (NM) Part 6: OSEK/VDX Implementation Language (OIL) v Introduction This part of ISO 17356 specifies a uniform communication environment for automotive control u
17、nit application software. It increases the portability of application software modules by defining common software communication interfaces and behaviour for internal communication communication within an electronic control unit (ECU) and external communication (communication between networked vehic
18、le nodes), which is independent of the communication protocol used. This part of ISO 17356 describes the behaviour within one ECU. It assumes that the communication environment described in this part of ISO 17356 is used together with an operating system that conforms to ISO 17356-3. For information
19、 on how to run the communication environment described in this part of ISO 17356 on operating systems that do not conform to ISO 17356-3, refer to Annex A. Requirements The following main requirements are fulfilled by this part of ISO 17356: General communication functionality This part of ISO 17356
20、 offers services to transfer data between tasks and/or interrupt service routines. Different tasks may reside in one and the same ECU (internal communication) or in different ECUs (external communication). Access to ISO 17356-4 services is only possible via the specified Application Program Interfac
21、e (API). Portability, reusability and interoperability of application software It is the aim of this part of ISO 17356 to support the portability, reusability and interoperability of application software. The API hides the differences between internal and external communication as well as different
22、communication protocols, bus systems and networks. Scalability This part of ISO 17356 ensures that an ISO 17356-4 implementation can run on many hardware platforms. The implementation requires only a minimum of hardware resources, therefore different levels of functionality (conformance classes) are
23、 provided. Support for ISO 17356-5 (Network Management-NM): Services to support Indirect NM are provided. Direct NM has no requirements of this part of ISO 17356. Communication concept Figure 1 shows the conceptual model of this part of ISO 17356 and its positioning within the architecture defined b
24、y ISO 17356. This model is presented for better understanding, but does not imply a particular implementation of this part of ISO 17356. BS ISO 17356-4:2005vi Figure 1 COMs layer model In this model, the scope of this part of ISO 17356 partly or entirely covers the following layers: Interaction Laye
25、r The Interaction Layer (IL) provides the ISO 17356-4 API which contains services for the transfer (send and receive operations) of messages. For external communication it uses services provided by the lower layers, whereas internal communication is handled entirely by the IL. Network Layer The Netw
26、ork Layer handles depending on the communication protocol used message segmentation/recombination and acknowledgement. It provides flow control mechanisms to enable the interfacing of communication peers featuring different levels of performance and capabilities. The Network Layer uses services prov
27、ided by the Data Link Layer. This part of ISO 17356 does not specify the Network Layer; it merely defines minimum requirements for the Network Layer to support all features of the IL. Data Link Layer The Data Link Layer provides the upper layers with services for the unacknowledged transfer of indiv
28、idual data packets (frames) over a network. Additionally, it provides services for the NM. This part of ISO 17356 does not specify the Data Link Layer; it merely defines minimum requirements for the Data Link Layer to support all features of the IL. BS ISO 17356-4:2005 vii Structure of this document
29、 In the following text, the specification chapters are described briefly. Clauses 1 to 5 are normative, the appendices are descriptive. Clause 1: Scope This clause describes the motivation and requirements for this part of ISO 17356, the conceptual model used and the structure of the document. Claus
30、e 2: Normative references Clause 3: Interaction Layer This clause describes the functionality of the IL of the ISO 17356-4 model and defines its API. Clause 4: Minimum requirements of lower communication layers This clause lists the requirements imposed by this part of ISO 17356 on the lower communi
31、cation layers (Network Layer and Data Link Layer) to support all features of the IL. Clause 5: Conformance Classes This clause specifies the Communication Conformance Classes, which allow the adaptation of the feature content of ISO 17356-4 implementations to the target systems requirements. Annex A
32、: Use of this part of ISO 17356 (Com) with an OS not conforming to ISO 17356-3 Annex A gives hints on how to run this part of ISO 17356 on operating systems that do not conform to ISO 17356-3. Annex B: Application notes Annex B provides information on how to meet specific application requirements wi
33、th the given ISO 17356-4 model. Annex C: Callouts Annex C supplies application examples for callouts. BS ISO 17356-4:2005blank 1Road vehicles Open interface for embedded automotive applications Part 4: OSEK/VDX Communication (COM) 1 Scope This part of ISO 17356-4 (COM) specifies a uniform communicat
34、ion environment for automatic control unit application software. It increases the portability of application software modules by defining common software communication interfaces and behaviours for internal communication (communication within an ECU) and external communication (communication between
35、 networked vehicle nodes), which is independent of the used communication protocol. 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 th
36、e referenced document (including any amendments) applies. ISO 17356-2, Road vehicles Open interface for embedded automotive applications Part 2 OSEK/VDX specifications for binding OS, COM and NM ISO 17356-3, Road vehicles Open interface for embedded automotive applications Part 3 OSEK/VDX Operating
37、System (OS) ISO 17356-5, Road vehicles Open interface for embedded automotive applications Part 5 OSEK/VDX Network Management (NM) ISO 17356-6, Road vehicles Open interface for embedded automotive applications Part 6 OSEK/VDX Implementation Language (OIL) 3 Interaction Layer 3.1 Overview 3.1.1 Prese
38、ntation The communication in this part of ISO 17356 is based on messages 1) . A message contains application- specific data. Messages and message properties are configured statically via OIL (ISO 17356-6). The content and usage of messages is not relevant to this part of ISO 17356. Messages with a l
39、ength of zero (see zero- length messages, Annex B) are allowed. 1) Messages are often called signals. Thus, COM offers a signal-based interface. BS ISO 17356-4:20052 In the case of internal communication, the Interaction Layer (IL) makes the message data immediately available to the receiver (see Fi
40、gure 2). In the case of external communication, the IL packs one or more messages into assigned Interaction Layer Protocol Data Units (I-PDU) and passes them to the underlying layer. The functionality of internal communication is a subset of the functionality of external communication. Internal-exte
41、rnal communication occurs when the same message is sent internally as well as externally. Administration of messages is done in the IL based on message objects. Message objects exist on the sending side (sending message object) and on the receiving side (receiving message object). Figure 2 Simplifie
42、d model for message transmission and reception in ISO 17356-4 The data that is communicated between the IL and the underlying layer is organized into I-PDUs which contain one or more messages (see Figure 2). A message shall occupy contiguous bits within an I-PDU and shall not be split across I-PDUs.
43、 Within an I-PDU messages are bit-aligned. The size of a message is specified in bits. The byte order (endianess) in a CPU can differ from the network representation or from other CPUs on the network. Therefore, to provide interoperability across the network, the IL provides a conversion from the ne
44、twork representation to the local CPU representation and vice versa, which is statically configured on a per- message basis. The IL offers an Application Program Interface (API) to handle messages. The API provides services for initialization, data transfer and communication management. Services tra
45、nsmitting messages over network are non-blocking. This implies, for example, that a service that sends a message is unable to return a final transmission status because the transfer to the network is still in progress. This part of ISO 17356 provides notification mechanisms for an application to det
46、ermine the status of a transmission or reception. The functionality of the IL can be extended by callouts. (3.8 contains a description of where callouts can be inserted.) BS ISO 17356-4:2005 3 3.1.2 Communication concept Senders and receivers of messages are either tasks or interrupt service routine
47、s (ISRs) in an OS. Messages are sent to sending message objects and received from receiving message objects. Message objects are identified using message identifiers. Message identifiers are assigned to message objects at system generation. This part of ISO 17356 supports communication from “m” send
48、ers to “n” receivers (m:n communication). Zero or more senders can send messages to the same sending message object. Sending message objects are configured to store messages in zero or more receiving message objects for internal communication and in zero or one I-PDUs for external communication. One
49、 or more sending message objects can be configured to store messages in the same I-PDU for external communication. An I-PDU can be received by zero or more CPUs. In each CPU which receives the I-PDU, each message contained in the I-PDU is stored in zero or more receiving message objects. Zero or more receivers can receive messages from a receiving message object (see Annex B for additional information). A receiving message object receives