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SAE J2735-Draft-Rev15 [issued: 01-30-07]
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110 -
This is an SAE Motor Vehicle Council draft document of the DSRC committee, subject to change.
8. EXTERNAL DATA ENTRIES
Data entries specified in Clauses 6 and 7 are also composed of message elements defined by other standards
bodies. These "foreign" elements are defined in the sections which follow. These definitions were taken from the
then-current adopted standards of these organizations when possible, and from the best available sources when
not. The referenced standards shall be consulted for further information regarding their proper use. Unless
otherwise noted in each entry, the below ASN.1 and XML definitions shall be taken as the governing definition
when used in this standard, even when a more current standard is adopted by the issuing organization.
Deployment needs to approach the elements in this section with caution as they are subject to change and can be
difficult to coordinate. It is important that the deployment have a firm grasp of the definitions to be used in this
area. When changes and improvements are made, ensure that all parties are involved and coordinated.
The productions of ASN.1 which follow shall be considered normative in nature. While the majority of the normative
content is reflected in the actual syntax of the ASN.1 some entries also have additional statements in the ASN.1
comments which shall be considered to be normative as well. In addition, the commentary provided with each
entry may also provide additional normative restrictions on the proper use of the entry which shall be followed. The
XML productions follow directly from the ASN.1 specifications and the same rules shall be applied.
8.1 Data Element: DE_Extent [ATIS]
Use: The spatial distance over which this message applies and should be presented to the driver. Under certain
conditions some messages may never be shown to the driver of a vehicle if they are short in duration and other
conflicting needs supercede the display until such time as the subject message is no longer relevant.
ASN.1 Representation:
Extent ::= ENUMERATED {
useInstantlyOnly (0),
useFor3meters (1),
useFor10meters (2),
useFor50meters (3),
useFor100meters (4),
useFor500meters (5),
useFor1000meters (6),
useFor5000meters (7),
forever (255) -- very wide area
}
-- encode as a single byte
XML Representation:
<xs:simpleType name="Extent" >
<xs:annotation>
<xs:appinfo>
useInstantlyOnly (0)
useFor3meters (1)
useFor10meters (2)
useFor50meters (3)
useFor100meters (4)
useFor500meters (5)
useFor1000meters (6)
useFor5000meters (7)
forever (255) -- very wide area
</xs:appinfo>
<xs:documentation>
encode as a single byte
</xs:documentation>
</xs:annotation>
<xs:union>
<xs:simpleType>
<xs:restriction base="xs:unsignedInt">