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

Page 52

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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

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