BECKHOFF AX2000 CANopen communication profile - Manual (Page 123)

A positioning movement can only be initiated by providing the setpoints through the 1
st
RPDO, follo-
wed by a start through the 2
nd
RPDO. This uses handshaking with New setpoint (control word) and
Setpoint acknowledge (status word).
a) Setpoint:
COB-ID Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7
301 F4 01 00 00 E8 03 00 00
b) Control word with new setpoint bit (Bit 4) set:
COB-ID Byte 0 Byte 1
201 1F 00
c) Wait until the CANopen status word signals Setpoint acknowledge (Bit 12): e.g.
COB-ID Byte 0 Byte 1 Byte 2
181 27 15 03
d) Control word is reset by the New setpoint bit (Bit 4) immediately:
COB-ID Byte 0 Byte 1
201 0F 00
e) Drive removes Setpoint acknowledge:
COB-ID Byte 0 Byte 1 Byte 2
181 27 01 03
Wait for the positioning to be completed:
COB-ID Byte 0 Byte 1 Byte 2
181 27 05 0A
6.1.7 ASCII Communication
It makes sense to use ASCII communication through PDOs, since they can be used more efficiently
in this way. This requires that the NMT status machine is in the operational status.
Example: Read the parameter T-tacho (see Setup Software Online Help).
(All data are hexadecimal, with the ASCII characters below, in square brackets.)
Direction COB-ID Byte 0 Byte 1 Byte 2 Byte 3 Byte 4 Byte 5 Byte 6 Byte 7
Master Þ AX2xxx 301
47 h
[G]
56 h
[V]
46 h
[F]
42 h
[B]
54 h
[T]
0D h
[CR]
0A h
[LF]
0 h
[NUL]
AX2xxx Þ Master 281
30 h
[0]
2E h
[.]
36 h
[6]
0 h
[NUL]
0 h
[NUL]
0 h
[NUL]
0 h
[NUL]
0 h
[NUL]
AX2xxx Þ Master 281
0D h
[CR]
0A h
[LF]
0 h
[NUL]
0 h
[NUL]
0 h
[NUL]
0 h
[NUL]
0 h
[NUL]
0 h
[NUL]
AX2xxx Þ Master 281
2D h
[-]
2D h
[-]
3E h
[>]
0 h
[NUL]
0 h
[NUL]
0 h
[NUL]
0 h
[NUL]
0 h
[NUL]
Explanation: In telegram 1, the master queries the GVFBT parameter, terminated by the
ASCII code CR LF. The last free byte is filled by NUL.
The response of the AX2xxx is made in telegram 2, with the value 0.6,
the terminating code CR LF, and the prompt “—>” for the next parameter or
command. The segmentation of the response into three telegrams is not mandatory,
but depends on the transmission rate that has been set and the internal
synchronization mechanism.
CANopen for AX2000/2500 123
BECKHOFF
07/2007
Appendix