Omron NY532-1500 Reference Manual page 333

ReferenceType (Position Type Selection)
You can select one of the following position types.
• _mcCommand: Command position (value calculated in the previous task period)
The master axis command position that was calculated in the previous task period is used for the
current period.
The command value that was calculated for the master axis in the last periodic task is used to cal-
culate the command position of the slave axis in the current period.
• _mcFeedback: Value obtained in the same task period
The actual position of the master axis that was obtained in the same task period is used.
• _mcLatestCommand: Command position (value calculated in the same task period)
The command position of the master axis that was calculated in the same task period is used.
This enables the use of information that is more recent than for _mcCommand. However, the axis
number of the master axis must be set lower than the axis number of the slave axis.
If the axis number of the slave axis is lower than the axis number of the master axis, Error will
change to TRUE. A Master/Slave Axis Numbers Not in Ascending Order error (error code: 5438
hex) will be output to ErrorID.
Precautions for Correct Use Precautions for Correct Use
Here, the task period is the primary period if the task is the primary periodic task and the task
period of the priority-5 periodic task if the task is the priority-5 periodic task. In the same way, the
periodic task is the primary periodic task or the priority-5 periodic task.
Additional Information
The command position that is calculated in the same task period enables greater precision in
synchronization than the command position that was calculated in the previous task period.
However, the axis number set for the Master (Master Axis) in the system-defined variable for
motion control must be lower than the axis number set for the Slave (Slave Axis) in the system-
defined variable for motion control.
Relationship between Axis Types and Position Types
The relationship between the axis types that you can monitor and position types that is monitored is
shown below.
Axis Type
Servo axis
Encoder axis
Virtual servo axis
Virtual encoder axis
* A Position Type Selection Out of Range error (error code 5430 hex) occurs when the instruction is executed.
NY-series Motion Control Instructions Reference Manual (W561)
_mcCommand or _mcLatestCommand
OK
*
No
OK
*
No
3 Axis Command Instructions
ReferenceType
_mcFeedback
OK
OK
OK
OK
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