CAN Communication
Identifier Allocation Scheme
EPOS4 Communication Guide
3-34
CCMC | 2019-11 | rel8759
3.4
Identifier Allocation Scheme
The default ID allocation scheme consists of a functional part (Function Code) and a Module ID, which
allows distinguishing between devices. The Module ID is assigned by DIP switches and a SDO Object.
Figure 3-24
CAN communication – Default identifier allocation scheme
This ID allocation scheme allows peer-to-peer communication between a single master device and up to
127 slave devices. It also supports broadcasting of non-confirmed NMT Services, SYNC and Node Guard-
ing.
The predefined master/slave connection set supports…
•
one emergency object,
•
one SDO,
•
four Receive PDOs and three Transmit PDOs and the
•
node guarding object.
Table 3-13
CAN communication – Objects of the default connection set
Object
Function Code
(binary)
Resulting COB-ID
Communication
Parameter at
Index
NMT
0000
0
–
SYNC
0001
128
(0080h)
1005h
EMERGENCY
129…255
(0081h-00FFh)
1014h
PDO1 (tx)
0011
385…511
(0181h-01FFh)
1800h
PDO1 (rx)
0100
513…639
(0201h-027Fh)
1400h
PDO2 (tx)
0101
641…8767
(0281h-02FFh)
1801h
PDO2 (rx)
0110
769…895
(0301h-037Fh)
1401h
PDO3 (tx)
0111
897…1023
(0381h-03FFh)
1802h
PDO3 (rx)
1000
1025…1151
(0401h-047Fh)
1402h
PDO4 (tx)
1001
1153…1279
(0481h-04FFh)
1803h
PDO4 (rx)
1010
1281…1407
(0501h-057Fh)
1403h
SDO1 (tx)
1011
1409…1535
(0581h-05FFh)
1200h
SDO1 (rx)
1100
1537…1663
(0601h-067Fh)
1200h