3 example of pdo usage, Example of pdo usage, Appendix – BECKHOFF AX2000 CANopen communication profile User Manual

Page 117

Advertising
background image

6.1.3

Example of PDO usage

Using all four possible PDOs in operation:

1. RPDO: PDO trajectory for one axis
2. RPDO: PDO control word and mode changeover
1. TPDO: PDO enhanced status
2. TPDO: PDO with incremental actual position, speed and operating mode display

Procedure:

Since the first RPDO is not available from the drive in the pre-defined form as required (

Þ 4.3.1) it

must be assembled. First, it is necessary to check whether the entries for the incremental setpoint
provision are available in mappable form.
This is the case with Object 2022

h

Sub-index 04

h

. So the 1st RPDO is selected:

COB-ID

Control byte

Index

Sub-

index

Data

Comment

Low byte

High byte

601

2F

00

26

00

h

25 00 00 00 select PDO 37 as 1

st

RPDO

581

60

00

26

00

h

00 00 00 00 response telegram

The freely mappable RPDO 37 has thus been selected. In the next step, data must be attached to
this PDO. This is done through the mapping parameter for the first RPDO:

COB-ID

Control byte

Index

Sub-

index

Data

Comment

Low byte

High byte

601

23

00

16

00

h

00 00 00 00 delete data for 1

st

RPDO

581

60

00

16

00

h

00 00 00 00 response telegram

601

23

00

16

01

h

20 04 22 20

data for first entry of the
1

st

RPDO

Object 2022

h

Sub-index 04

h

,

data length: 32 bit

581

60

00

16

01

h

00 00 00 00 response telegram

The data content of the first PDO has now been defined, and it includes 4 bytes of user data.

Next, the communication parameters can be defined:

The system must react to COB-ID 201

h

as standard. So Sub-index 01

h

must remain set to the

default value. But the drive must react to every SYNC Object, so a value of 1 must be applied to
Sub-index 2:

COB-ID

Control byte

Index

Sub-

index

Data

Comment

Low byte

High byte

601

2F

00

14

02

h

01 00 00 00 reaction to every SYNC

581

60

00

14

02

h

00 00 00 00 response telegram

The 2

nd

RPDO is to have two components: the CANopen control word (Object 6040

h

Sub-index

00

h

) and the Object for changing the operating mode (Object 6060

h

Sub-index 00

h

).

The selection of the 2

nd

RPDO is made as follows:

COB-ID

Control byte

Index

Sub-

index

Data

Comment

Low byte

High byte

601

2F

01

26

00

h

26 00 00 00 select PDO 38 as 2

nd

RPDO

581

60

01

26

00

h

00 00 00 00 response telegram

CANopen for AX2000/2500

117

BECKHOFF

07/2007

Appendix

Advertising