3 transmission type, Transmission type, 11 system bus "can on board – Lenze 8400 StateLine User Manual

Page 519

Advertising
background image

Lenze · 8400 StateLine · Reference manual · DMS 12.0 EN · 06/2014 · TD05/TD14

519

11

System bus "CAN on board"

11.8

Process data transfer

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

11.8.3

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 special 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 transmitted (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 transmitted 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

AND

1 ... 240

-

254, 255

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

Synchronous - RTR only

253

Asynchronous - RTR only

254, 255

Asynchronous - manufacturer-specific / device profile-specific:

If this value is entered, the PDO transmission is event-controlled or cyclic.

(Note: The values "254" and "255" have the same meaning).

For a cyclic transmission, a cycle time must be entered for the respective PDO. In this case,

cyclic transmission takes place in addition to event-controlled transmission.

Advertising