Synchronizing Host Applications with Onboard Programs LabVIEW Diagram

Tip  Refer to NI-Motion\Documentation\Examples\NI-Motion User Manual\ for the LabVIEW VIs for these examples.

This example moves axis 1 between target positions of 5000 and –5000. The host reads the target position only after the move has completed, and the new target position has been calculated. The following figure shows the code that runs as an onboard program.

1  Load Constant to Variable	6  Insert Program Label	11  Multiply Variables
2  Load Constant to Variable	7  Load Target Position	12  Set User Status MOMO
3  Begin Program Storage	8  Start Motion	13  Jump to Label on Condition
4  Set Operation Mode	9  Select MOMO	14  End Program Storage
5  Load Velocity	10  Wait on Condition	15  Motion Error Handler

The following figure shows the code that runs on the host.

1  Read Move Complete Status	2  Set User Status MOMO	3  Read Variable

Note  As the host is polling a register on the motion controller, it is not invoking the Host Communication Task on the real-time operating system on the motion controller. Therefore, the onboard programs executing are not preempted. In this situation, the onboard programs run deterministically.