4 transmission type, Transmission type, Communication manual 8400 motec canopen – Lenze E84DGFCC User Manual
Page 52

Communication manual 8400 motec CANopen
Process data transfer
Transmission type
52
L
EDS84DMOTCAN EN 3.0 - 11/2011
8.4
Transmission type
Process data objects can be transmitted in an event-controlled or time-controlled manner.
The below table shows that it is possible to combine the different methods by means of
logic operations (AND, OR):
Event-controlled
The PDO is sent when a certain device-internal event has occurred, e.g. when the data
contents of the TPDO have changed or when a transmission cycle time has elapsed
Synchronous transmission
A TPDO (or RPDO) is sent (or received) after the device has received a sync telegram
(COB-ID 0x80).
Cyclic transmission
The cyclic transmission of PDOs takes place when the transmission cycle time has
elapsed.
Polled via RTR
A TPDO is sent when another device requests it by means of a data request telegram
(RTR remote transmit request). For this purpose, the data requester (e.g. the master)
sends the data request telegram with the COB-ID of the TPDO requested to be sent. The
receiver recognises the RTR and transmits the corresponding PDO.
Transmission type
PDO transmission
Logic combination of
different
transmission types
cyclic
synchronous
event-controlled
0
z
z
AND
1 ... 240
z
z
AND
254
z
z
OR
Transmission type
Description
0
Synchronous and acyclic:
The PDO is transmitted on an event-controlled basis with every sync (e.g. when a bit change
occurs in the PDO).
1 ... 240
Synchronous and cyclic (sync-controlled with response):
• Selection n = 1: The PDO is transmitted with every sync.
• Selection 1 < n ≤ 240: The PDO is transmitted with every n-th sync.
241 ... 251
Reserved
252, 253
RTR-controlled manner is not permissible.
254
Event-controlled with cyclic transmission:
If this value is entered, the PDO is transferred in an event-controlled or cyclic manner. (The
values "254" and "255" are equivalent).
For a cyclic transmission, a cycle time must be set for the respective PDO. In this case, cyclic
transmission takes place in addition to event-controlled transmission.
255
Not permissible