VIPA CPU 21 Series, Manual

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Chapter 8 Deployment CPU 21xCAN Manual VIPA CPU 21x
8-18 HB103E - Rev. 05/45
For access to the object directory, the S ervice- D ata- O bject (SDO) is used.
The SDO allows you a read or write access to the object directory. In the
CAL-Layer-7-Protocol you find the specification of the Multiplexed-Domain-
Transfer-Protocol that is used by the SDOs. This protocol allows you to
transfer data with any length. At need, the messages are divided into
several CAN messages with identical identifier (segmentation). A SDO is
transferred acknowledged, i.e. every reception of a message is
acknowledged.
Note!
A more detailed description of the SDO telegrams is to find in the CiA norm
DS-301.
In the following only the error messages are described that may occur at a
wrong parameter communication.
Every CPU has the SFC 219 integrated. This allows you to start a SDO
read or write access from your PLC program to the CAN master.
You address your master via the plug-in location and the destination slave
via its CAN address. The process data is defined by index and subindex.
Via SDO every access transfers max. one data word process data. The
SFC 219 contains the following parameters:
Control parameter: 1: Start the order
depending on plug-in location no.
0: for addressing the integrated CAN master
1 ... 32: for addressing stand-alone System 200V CAN master
Address of the CANopen node (1...127)
40h, 60h: Read SDO 61h: Write SDO (undefined length)
23h: Write SDO (1 DWORD)
2Bh: Write SDO (1 WORD)
2Fh: Write SDO ( 1 BYTE)
CANopen Index
CANopen Subindex
SDO
SFC 219 CAN_TLGR
SDO request to CAN
master
Request
Slot_Master
NodelD
Transfer type
Index
Subindex