Proprietary protocol
General
Because J1939 documents do not define a standard communication protocol for systems like EHPS, a
proprietary one has been defined on top of the existing common mechanisms described in previous
section. The proprietary protocol covers issues related to the communication with sensors, configuration,
status information, etc. Detailed information is available in the following sections.
The following general rules apply:
•
the time delay between messages marked as “when needed” shall not be less than 100 ms
•
PVED-CL shall respond within 200 ms, with exception for CommitDataResponse – 5000 ms
•
a response timeout shall be 500 ms (does not apply to CommitDataResponse message)
•
a not allowed command is ignored what results in no response sent back. Timeout policy shall apply
•
as a proprietary protocol is in use, default message priority shall be set to 6
PVED-CL’s can receive messages from selected nodes only. The source addresses of the vehicle speed
sensor, the MMI controller, the high priority external set-point controller as well as the configuration tool
and PVED-CL itself are configurable.
The default factory programmed values
Node
Default Source Address
PVED-CL
19
High priority external set-point controller
28
Vehicle speed sensor
251
MMI controller
252
Configuration/diagnostic tool
253
Communication with sensors and steering devices
In general, most of this type communication is performed with 11bit ID messages. More details about
message formats can be found in chapter
Communication with sensors and steering devices
on page 9.
A sensor is expected to periodically broadcast the data. A lack of data from the mapped sensor (with
exception for high priority set-point controller) causes PVED-CL to fail silent or enter the reduced mode,
depending on the configuration data. The timeouts are as follows:
The timeouts
Sensor or Steering Device:
Timeout [ms]
Steering wheel sensor
100
High priority steering device
100
Low priority steering device
100
Primary steered wheel angle/position sensor
60
Redundant steered wheel angle/position sensor
60
Vehicle speed sensor
160
Configuration
PVED-CL’s configuration memory contain parameters which identify the system components and control
the device’s behaviour. These parameters can be set up with a configuration tool.
The following operations are available:
Technical Information
PVED-CL Communication Protocol, version 1.38 Technical Information
Communications
11079551 • Rev BA • July 2014
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