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NI 9503 C Series Stepper Drive Modules and SoftMotion Module
Figure 5.
9503 Stepper Drive (Getting Started) User-Defined Varia
b
les
The following table briefly describes each UDV used in the project. Refer to
Adding
User-Defined Variables for Use With a UDV Axis
in the
SoftMotion Module Help
for more
information about each UDV.
SoftMotion Engine to FPGA Communication
Each User-Defined Variable communicates information between the SoftMotion Engine and the
LabVIEW FPGA Module. These UDVs are used directly with the Drive Interface FPGA VIs in
specific loops on the block diagram. Complete the following steps to open the FPGA VI and
display the block diagram.
1.
Expand the
FPGA Target
item in the LabVIEW Project Explorer window.
2.
Double-click the
Stepper Drive (Getting Started) - FPGA.vi
item to open the VI.
3.
Select
Window»Show Block Diagram
to open the FPGA VI block diagram.
The following table briefly describes each FPGA VI loop used in the project.
Table 1.
Stepper Drive (Getting Started) UDV Descriptions
UDV Name
Description
Axis 1.Control Register
Contains information used to control the state and operating
mode of the device.
Axis 1.Mailbox
(FPGA to Host)
Contains information used to provide configuration and other
data from FPGA to the SoftMotion Engine.
Axis 1.Mailbox
(Host to FPGA)
Contains information used to provide configuration and other
data from the SoftMotion Engine to FPGA.
Axis 1.Position Setpoint
Specifies the position setpoint.
Axis 1.Status Register
Contains information used to report status and operation mode
information from the device to the system.
Axis 1.Steps Generated
Returns the current step count of the stepper generator taking
into account the direction. This value is based on actual steps
generated, not feedback position, and may not exactly match the
feedback position.
