J1939/ISOBUS compliance
Network Management Protocol (NMP)
To make PVED-CL able to work in CAN J1939 networks, the following parts of NMP have been
implemented:
•
Address Claimed
•
Request for Address Claimed response
PVED-CL claims it address on power-on, after any won address arbitration and when requested to do so.
However, please note that because of some platform and software architecture constraints, PVED-CL may
claim its address even when it’s not needed. This is triggered by a RequestParameterGroup message –
no matter which node has sent it and which one the message is addressed to – as illustrated on figure
below.
Identification
There are 2 items which identify PVED-CL:
•
Source Address – available in all 29bit ID messages sent by PVED-CL
•
NAME – broadcast while claiming the address
Apart from this, the protocol supports the following proprietary identification:
•
PVED Serial Number available as a read-only parameter at index 65001
•
Sales Order Number at index 65002
•
Software Version Number at index 65003
•
Parameter Definition File at index 65004
SoftwareID (pgn65242) and ComponentID (pgn65259) defined by [J1939-71] are not available.
Application layer
Some steering functionality requires the Wheel Based Vehicle Speed signal (spn84) available in
pgn65265 – for more detailed information see
Vehicle speed
on page 15. The standardized guidance
messages are available in pgn44288 (Guidance System Command) and pgn44032 (Guidance Machine
Status). Further details see
GuidanceSystemCommand
on page 33.
PVED-CL supports Request PG message, but recognizes only requests for Address Claimed (pgn60928),
DM1 (pgn65226), DM2 (pgn65227) and DM3 (pgn65228). All other requests, if addressed explicitly to
PVED-CL, are answered with NACK (pgn59392).
Please note the following limitations:
•
Only 4 ACK/NACK messages can be buffered for transmission. Other requests will be ignored
•
If Request PG messages are sent too fast (with an interval less than 20 ms), some messages may be
lost.
Diagnostics
PVED-CL supports the following items defined by the J1939 diagnostic protocol [J1939-73]:
•
DM1 – Active Diagnostic Trouble Codes
•
DM2 – Previously Active Diagnostic Trouble Codes
•
DM3 – Diagnostic Data Clear/Reset for Previously Active DTCs
A request for DM3 results in resetting the Occurrence Counts for Previously Active DTCs.
Technical Information
PVED-CL Communication Protocol, version 1.38 Technical Information
Communications
6
11079551 • Rev BA • July 2014