Lika XAC77 FB, User Manual

Page: 49 / 54

XAC77 Profibus-DP
®
Preset value
when any Class is set
(Master  Slave)
Byte 1 2 3 4
Bit 31-24 23-16 15-8 7-0
Data 2 31 to 2 24 2 23 to 2 16 2 15 to 2 8 2 7 to 2 0
Preset value is the process current value, that is: a value is set for a physical
position of the encoder shaft. When the axis reaches the set physical position
the
Preset value is transmitted.
- If Scaling function control = disabled
Preset value < “Total hardware resolution”.
- If Scaling function control = enabled
Preset value < Total resolution .
The Preset value is sent from Master to Slave in Data_Exchange mode by setting
bit 31 = “1” for 3 cycles.
Example
Preset value to be set = 0000 1000hex
actual position = 0005 5000hex
Byte 1 2 3 4
Cycle
Bit 31-24 23-16 15-8 7-0
1°
M  S 80 00 10 00
S  M 00 05 50 00
2°
M

S 80 00 10 00
S  M 00 05 50 00
3°
M  S 80 00 10 00
S  M 00 00 10 00
We suggest setting the Preset value when the shaft is in stop.
The new Preset value is saved immediately after receipt.
MAN XAC77 PX I_E 1.0.odt 49 Profibus® interface