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
147
Example of a short message documentation:
But even if the aggregate manufacturer only provides a short documentation, the function parameters
can be derived from the identifier. In addition to the ID, the "transmission repetition rate" and the
meaning of the data fields are also always needed.
If the protocol messages are not manufacturer-specific, the standard SAE J1939 or ISO 11992 can
also serve as information source.
Structure of the identifier 0CF00203
16
:
PRIO, reserv., PG PF + PS SA / DA
0 C F 0 0 2 0 3
As these values are hexadecimal numbers of which individual bits are sometimes needed, the
numbers must be further broken down:
SA / DA Source / destination address (hexadecimal) Source / destination address (decimal)
0 3 00 03 0 3
PF PDU format (PF) (hexadecimal) PDU format (PF) (decimal)
F 0 0F 00 16 0
PS PDU specific (PS) (hexadecimal) PDU specific (PS) (decimal)
0 2 00 02 0 2
PRIO, reserv., PG PRIO, reserv., PG (binary)
0 C 0000 1100
Out of the 8 bits (0C
16
) only the 5 least significant bits are needed:
Not required Priority Res. PG
x x x 0
2
1
2
1
2
0
2
0
2
03
10
0
10
0
10
Further typical combinations for "PG, reserv., PG"
18
16
:
Not required Priority Res. PG
x x x 1
2
1
2
0
2
0
2
0
2
6
10
0
10
0
10
1C
16
:
Not required Priority Res. PG
x x x 1
2
1
2
1
2
0
2
0
2
7
10
0
10
0
10