Beckhoff – BECKHOFF AX2000 CANopen communication profile User Manual
Page 126

After the Trajectory PDO has been mapped to the two axes, the communication parameters for
both must be set so that they respond to the same Communication Object Identifier (COB-ID). The
COB-ID for the first station can keep its default value of 301, the one for the second station can
then be re-mapped to this setting:
COB-ID
Control byte
Index
Sub-
index
Data
Comment
Low byte
High byte
602
23
01
14
01
h
01 03 00 00
map 2
nd
RPDO for 2
nd
axis to 301
582
60
01
14
01
h
00 00 00 00
Both stations will now respond to the same COB-ID 301.
Object 2721
h
Sub-index 00
h
can then be used to define which portion of the 8 byte data field is
used by each axis for its trajectory information. The value 0 selects Bytes 0 ... 3 of the data, and the
value 1 selects bytes 4 ... 7.
COB-ID
Control byte
Index
Sub-
index
Data
Comment
Low byte
High byte
601
2F
21
27
00
h
00 00 00 00
1
st
axis takes data from
Bytes 0 ... 3
581
60
21
27
00
h
00 00 00 00
602
2F
21
27
00
h
04 00 00 00
2
nd
axis takes data from
Bytes 4 ... 7
582
60
21
27
00
h
00 00 00 00
The actual positions of the axes are to be returned as incremental actual positions to the controls.
The second transmit-PDO in each case is therefore mapped to TPDO 33 Incremental actual posi-
tion (33
d
= 21
h
):
COB-ID
Control byte
Index
Sub-
index
Data
Comment
Low byte
High byte
601
2F
01
2A
00
h
21 00 00 00
set the Trajectory PDO for
1
st
axis
581
60
01
2A
00
h
00 00 00 00
602
2F
01
2A
00
h
21 00 00 00
set the Trajectory PDO for
2
nd
axis
582
60
01
2A
00
h
00 00 00 00
Here it is assumed that both amplifiers accept new trajectory values with every SYNC command,
and have to return their incremental position values. The communication parameters must be set
accordingly:
COB-ID
Control byte
Index
Sub-
index
Data
Comment
Low byte
High byte
601
2F
01
14
02
h
01 00 00 00
RPDO 2, axis 1, reaction for
every SYNC
581
60
01
14
02
h
00 00 00 00
602
2F
01
14
02
h
01 00 00 00
RPDO 2, axis 2, reaction for
every SYNC
582
60
01
14
02
h
00 00 00 00
601
2F
01
18
02
h
01 00 00 00
TPDO 2, axis 1, reaction for
every SYNC
581
60
01
18
02
h
00 00 00 00
602
2F
01
18
02
h
01 00 00 00
TPDO 2, axis 2, reaction for
every SYNC
582
60
01
18
02
h
00 00 00 00
In order to be able to make trajectory movements, both servo amplifiers must be operating in the
appropriate mode. This is set through Index 6060
h
:
COB-ID
Control byte
Index
Sub-
index
Data
Comment
Low byte
High byte
601
2F
60
60
00
h
FA 00 00 00 set trajectory mode for axis 1
581
60
60
60
00
h
00 00 00 00
602
2F
60
60
00
h
FA 00 00 00
set trajectory mode for axis 2
582
60
60
60
00
h
00 00 00 00
126
CANopen for AX2000/2500
Appendix
07/2007
BECKHOFF