BECKHOFF AX2000 CANopen communication profile - Manual (Page 125)

6.2 Special Applications
6.2.1 External Trajectory
6.2.1.1 Position controller in the servo amplifier
This example shows the situation where 2 axes each receive position setpoints through RPDO 33
Trajectory.
Controller structure for the position controller within the servo amplifier:
Description
All data are hexadecimal. In the example, the two axes in the system have the station addresses 1
and 2.
Examples of telegrams and responses:
Conditions:
l The resolution that is to be used within one motor turn must be defined for both axes: PRBASE
set to 16 or 20 bit resolution for 1 turn.
l The time raster for trajectory inputs must be set through the PTBASE parameter.
Here one unit has a value of 250 microseconds: for example, PTBASE = 8 produces a 2 ms
time raster.
l The parameters must be saved in the EEPROM.
l The saved values only become available after a reset.
The Trajectory PDO contains 2 trajectory setpoints, and can be transmitted simultaneously to seve-
ral stations, whereby each station can extract the relevant trajectory data.
Map the second receive-PDO for both axes to RPDO 33 Trajectory (33
d
= 21
h
):
COB-ID Control byte Index Sub-
index
Data Comment
Low byte High byte
601 2F 01 26 00 h 21 00 00 00 set the Trajectory PDO for
1
st
axis 581 60 01 26 00 h 00 00 00 00
602 2F 01 26 00 h 21 00 00 00 set the Trajectory PDO for
2
nd axis 582 60 01 26 00 h 00 00 00 00
CANopen for AX2000/2500 125
BECKHOFF
07/2007
Appendix
Position setpoints
SYNC
RPDO Trajektory
No. 33
Position controller
speed setpoint
Position + Status
TPDO actual position in increments
No. 33