
4th edition, 9-11-2018
7000.05050, 4th edition, 9-11-2018
7000.05050
CANopen protocol description
26
3.7
SYNC object
The SYNC object is a message without any user data. The SYNC object is used to trigger syn-
chronous PDOs and at the same time to start processes on various items of equipment.
The identifier of the SYNC objects is set in the object dictionary under the index 0x1005 (by
default 0x80).
3.7.1
Triggering synchronous PDOs
Synchronous RxPDO:
The command transmitted with the PDO is not executed until a SYNC
object is received. The transmission types 1 to 240 of an RxPDO are identical to transmission
type 0.
Synchronous TxPDO:
The synchronous TxPDOs with the current data are sent immediately
after a SYNC object is received.
Fig. 6:
TxPDO with SYNC chart
11-bit identifier
0 bytes of user data
0x80
no user data
In order that an SYNC object triggers a PDO, the transmission type of the PDO to be
triggered must be set accordingly (see Tab. 5).
The nodes can also be grouped by transmission types 1-240.
Time
S
YN
C
O
b
je
c
t
S
yn
c
hronous PDO
Asyn
c
hronous PDO