 Telematics Applications for Transport Library
 Document item |
|
 Title : |
ROSIN - TR 1045 - Report describing the specification work for the application interface |
| Author : |
H. Kirrmann; P. Vivegnis; X. Thibault |
| Ref. No : |
TR1045 D4.1 |
| Date : |
01/04/97 |
| Size : |
68 pages |
Exec Summary : |
This document deliverable D04.1 Report describing the specification work of the application interface defines a framework for standard application interface dealing with the data communication between programmable electronic equipment. Moreover, the Deliverable defines a general method to describe application interface.
It specifies how devices are structured and messages are defined (including formats and semantics).In the Train Communication Network, interoperability of interconnected devices and vehicles of different origin depends on a precise definition of the exchanged data, from the application down to the bit level.
Each variable and each object is identified by its name to which an object type, an object representation and an object semantic is attached.
A formal data representation is the base of the specification of the application data, which groups such as the UIC 5R or the IEC SGA develop.
The formal data representation allows to describe variables and messages exported by the different devices as a sequence of named data types.
The IEC Train Communication Network specifies in Clause 2 (Real-Time protocols) a data representation in a graphical form.
This notation is used extensively in Clause 5 (Network Management). However, this graphical representation is not machine-readable, and programmers have to translate it to the data representation in their programming language such as "C", an error-prone process.
To remove ambiguities, this document introduces a formalism of the TCN data representation based on ISO?s Abstract Syntax Notation Nr. 1, (ASN.1).
This language is independent from the programming language used by the application.
The present proposal introduces minor deviations from the TCN standard, most of them being in the naming conventions. To precise the conventions from the application to the bus, this document explains :how to map bus data formats to the application data form at four different levels:
- on the bus
- in the Traffic Store
- in the Application Memory
- in the application programming language.
Note - this document does not supersede the current IEC 9/413/CDV, it is intended to clarify it using a different notation and precise the mapping.
This document is splitted in 4 parts.
· The first chapter gives an introduction to remind scope and references of the standard application interface WorkPackage within ROSIN project.
· Chapter 2 defines the framework which enables the description of data. It defines a formalism for the representation of data based on ISO?s an Abstract Syntax Notation, together with compact encoding rules suited for the transmission of real-time data. It defines the mapping to the application programming, to the storage and to the transmission on the bus.
· Chapter 3 specifies a general method to describe communication functions. It gives first the reference model with definitions and then presents the methodology to describe an application interface.
· Chapter 4 gives the conclusion and two annexes are added :1.
In Annex I , descriptions of simple and structured data representation are given in details. 2. In Annex II , an application interface ( HVAC interface ) is described with the methodology given in chapter 3.
This document consists of 1 volume rosin d4.1.pdf |
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