IFM Electronic Ecomat 100 ecomatmobile SmartController CR2500, Системное руководство

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ifm System Manual ecomat mobile SmartController (CR2500, CR2502) V05
CAN in the ecomatmobile controller Use of the CAN interfaces to SAE J1939
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8.9 Use of the CAN interfaces to SAE J1939
The CAN interfaces in the ecomat mobile controllers can also be used for communication with special
bus protocols for drive technology and utility vehicles. For these protocols the CAN controller of the
2nd interface is switched to the "extended mode". This means that the CAN messages are transferred
with a 29-bit identifier. Due to the longer identifier numerous messages can be directly assigned to the
identifier.
For writing the protocol this advantage was used and certain messages were combined in ID groups.
The ID assignment is specified in the standards SAE J1939 and ISO 11992. The protocol of
ISO 11992 is based on the protocol of SAE J1939.
Standard Application area
SAE J1939 Drive management
(is possible with this controller)
ISO 11992 Truck & Trailer interface
(requires other hardware because of higher voltage levels, e.g.
SmartController CR2501)
The 29-bit identifier consists of two parts:
- an 11-bit ID and
- an 18-bit ID.
As for the software protocol the two standards do not differ because ISO 11992 is based on
SAE J1939. Concerning the hardware interface, however, there is one difference: higher voltage level
for ISO 11992. Therefore controllers with a modified CAN interface are required for the communication
of aggregates with the interface ISO 11992 (e.g. SmartController CR2501).
NOTE
To use the functions to SAE J1939 the protocol description of the aggregate manufacturer (e.g. for
motors, gears) is definitely needed. For the messages implemented in the aggregate control device this
description must be used because not every manufacturer implements all messages or implementation
is not useful for all aggregates.
Table: structure of the identifier
Priority Rese
rved
Data page PDU format PDU s
pec
ific
Source / destination address
29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1
The following information and tools should be available to develop programs for functions to
SAE J1939:
•
List of the data to be used by the aggregates
•
Overview list of the aggregate manufacturer with all relevant data
•
CAN monitor with 29-bit support
•
If required, the standard SAE J1939