ISO PAS 17684:2003 pdf download Transport information and control systems — In-vehicule navigation systems — ITS message set translator to ASN.1 format definitions
Scope
This Publicly Available Specification specifies a method that can be used to define navigation message sets intabular form with a subsequent translation into a corresponding ASN.1 description. An intermediate languagecalled Descriptor Normal Form (DNF), which is a subset of ASN.1, is specified and used as an intermediatedescription between a tabular form and its ASN.1 description.
A tabular-form message-set description language called Message Set Tabular Form (MSTF) is included as anexample of a tabular form definition.
2 Normative references
The following referenced documents are indispensable for the application of this document. For datedreferences, only the edition cited applies. For undated references, the latest edition of the referenceddocument (including any amendments) applies.
ISO/EC 8824-1:1998, Information technology – Abstract Syntax Notation One (ASN.1): Specification of basicnotation – Part 1
ISO/IEC 10646-1:2000，Information technology- Universal Multiple-Octet Coded Character Set (UCS)Part 1: Architecture and Basic Multilinqual Plane
3Terms and definitions
For the purposes of this document, the following terms and definitions apply. The following terms are definedin ISO/EC 8824-1:1998 specification, bit string type, boolean type, character, character string types, choicetypes, component type, encoding, (ASN.1) encoding rules, enumerated types, false, integer type, module, nulype, octetstring type, real type, recursive definitions, selection types, sequence types, sequence-of typesspacing character, simple type, tag, true, type, type reference name, value, value set, white-space.
3,1
DNF character set
set of characters used in the DNF notation
NOTESee 5.4
3.2
floating-point number
number capable of being specified by the formula M x 10E where M and E are two integers called themantissa and the exponent. respectively
3.3
floating-point type
type consisting of all possible floating-point numbers plus the two values +oo and -.o
NOTEThe floating-point type is a subset of the real type in ASN.1. The real type accommodates bases other than 10
3.4
items
named sequences of characters from the DNF character set which are used to form the DNF notation
NOTESee 5.4.
Message Set Tabular Form description
4.1General
Message Set Tabular Form (MSTF) describes a message set by message components. A messagecomponent is defined by a line or lines, where a line consists of a sequence of boxes or cells. Each celcontains either a string of characters or is empty. A string of characters contained in a cell may be one of thefollowing component items:
a reserved word
a data type;
a data item;
a special indicator composed of one or two special characters:
a comment denoted by the special indicator “/”at the beginning of the comment character string.
Some of the data items used in MSTF are DNF identifiers (see 5.5.2). These component items are arranged incells to form a line in accordance with the rules for MSTF line format, and then the lines are structured to forma message component in MSTF. Major message components are structured in a block of lines where a blockis separated by a line of empty cells.
The first message component of a message set is the TITLE component
4.2 MSTF description
4.2.1Character set
The characters that can appear in MSTF are the same characters used in DNF (see 5.4.1).