Note the structure of the DPV1 telegram

Structure of the DPV1 telegram for write and read access.

Index

100

Slot number

Position of the EtherCAT Terminal, absolute position plus 1

Structure

Meaning

Length in bytes

CoE Index

CoE index number.

2

COE subindex

COE subindex number.

1

READ/ WRITE

0-read/ 1-write.

1

Length

Length of the data that is to be written. During reading, this can be zero.

4

Data

Data, only required for writing.

n

If you use virtual slaves, the slot number must contain the actual terminal position, not the slot position of the EtherCAT Terminal.

Example

You want to read the COE data of EtherCAT Terminal EL3154. This EtherCAT Terminal is configured in TwinCAT under slave 2 (virtual slave).

Distribution of the EtherCAT device in TwinCAT over two slaves.

Slave 1

Slave 2 (virtual slave)

EK3100

CtrlStatus

EL1008

EL2008

EL3062

EK1110

EK3100

CtrlStatus

EK1100

EL2008

EL1008

EL3154

PROFIBUS address: 11

PROFIBUS address: 12. The non-visible EL9011 is omitted.

In this example EtherCAT Terminal EL3154 has the slot number 9. The CtrlStatus DWORD module is not included in the count for the EK3100 virtual slave.

Distribution of the slot numbers across the EtherCAT devices.

Slave 1

Slave 2 (virtual slave)

Slot number

2

3

4

5

6

7

8

9

EK3100

EL1008

EL2008

EL3062

EK1110

EK1100

EL2008

EL1008

EL3154

PROFIBUS address: 11

PROFIBUS address: 12. The non-visible EL9011 is omitted.

Note the structure of the DPV1 telegram 1:

Reading CoE data

To read CoE data, the data to be read must first be written with a DPV1-Write, and only then can the data be read with a DPV1-READ.