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SAE J2735-Draft-Rev26 [issued: 09-18-08]
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171 -
This is an SAE Motor Vehicle Council draft document of the DSRC committee, subject to change.
7.115 Data Element: DE_SignalLightState
Use: A date element indicating the current (or the next) signal state of all lights pertaining to a particular
known lane or movement (set of lanes). Used in the the SPAT frame. The data element is an integer value
which is typically encoded with only the lower bits of significance being sent, therefore allowing shorter
payload byte counts when used. See the ColorState data element for suitable encoding values for each
section.
ASN.1 Representation:
SignalLightState ::= INTEGER (0..536870912)
-- The below bit ranges will map to each type of direction
-- using the 4 bits defined by the ColorState
-- None (circular) 1st ~ 4th bits 1 ~ 4
-- Left-Arrow 5 ~ 8
-- Right-Arrow 9 ~ 12
-- Through- Arrow (straight ahead) 13 ~ 16
-- 45 Degree Left Arrow (soft arrow) 17 ~ 20
-- 45 Degree Right Arrow (soft arrow) 21 ~ 24
-- U-turn light 25 ~ 28
-- Reserved1 29 ~ 32
XML Representation:
<xs:simpleType name="SignalLightState" >
<xs:annotation>
<xs:documentation>
The below bit ranges will map to each type of direction
using the 4 bits defined by the ColorState
None (circular) 1st ~ 4th bits 1 ~ 4
Left-Arrow 5 ~ 8
Right-Arrow 9 ~ 12
Through- Arrow (straight ahead) 13 ~ 16
45 Degree Left Arrow (soft arrow) 17 ~ 20
45 Degree Right Arrow (soft arrow) 21 ~ 24
U-turn light 25 ~ 28
Reserved1 29 ~ 32
</xs:documentation>
</xs:annotation>
<xs:restriction base="xs:unsignedInt">
<xs:maxInclusive value="536870912"/>
</xs:restriction>
</xs:simpleType>
Used By: This entry is used directly by one other data structure in this standard, a DF called
DF_MovementState <ASN> <XML>. In addition, this item may be used by data structures in other
ITS standards.
Remarks: Note that when used in the movement data frames the signal state appears twice for motorized
vehicle lanes, once for the current state, and once for the next "yellow" phase (when the current state is not
simply red). For stopped signals (red states) no yellow phase data is needed, nor is it present for lanes
states which deal with trains. Pedestrian lanes also have two such signal states, one for the period of the
walk time and one for the warning time at the end of walk.
7.116 Data Element: DE_SignalReqScheme
Use: The SignalReqScheme data element is used in a priority or preempt request frame to select which
preempt or priority controller sequence is to be activated. The data element has either a priority value or a
preemption value, depending on the setting of the MSB and what data frame it is used in.
A value of B'1111' indicates a request for cabinet flash when the data element is used in a preempt. The
value B'0111' is reserved when used for a priority request. The value B'000' is reserved.
ASN.1 Representation:
SignalReqScheme ::= OCTET STRING (SIZE(1))
-- Encoded as follows:
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