LabVIEW 2017 SoftMotion Module Bug Fixes


The following items are the IDs and titles of a subset of issues fixed between the release of the LabVIEW 2016 SoftMotion Module and the LabVIEW 2017 SoftMotion Module. If you have a CAR ID, you can search this list to validate that the issue has been fixed.

Bug Fixes

The following items are Bug Fixes in the LabVIEW 2017 SoftMotion Module.

ID Fixed Issue Issue Details
583192 SDI Axes do not implement the Smoothing attribute on reference moves On other SoftMotion axes, the Smoothing attribute calculates suitable acceleration values when supplied the position and velocity of a move. Because reference moves (home, limit, and index moves) are performed entirely by the EtherCAT drive, SoftMotion does not perform trajectory generation for these moves, and an acceleration and deceleration value of 0 will be used if none is commanded.
591142 SDI Axes do not have Home Switch Enabled by default or available in Axis Configuration dialog SoftMotion Drive Interface (SDI) Plug-in axes (third party EtherCAT drives) do not have the ability to set the Home Switch as enabled. Even though homing moves will be handled correctly by the drive, the Read: Motion I/O method does not show if the home switch is active.
607840 SoftMotion Drive Interface (SDI) VIs will not deploy when SoftMotion is not licensed The Axis:Execute Plugin Read and Write methods require licensing and will not deploy to a real-time target if SoftMotion is not licensed. This prevents the use of SDI axes when SoftMotion is not licensed on the development computer.
613626 Position Capture on SDI and UDV Axes do not handle position rollover SoftMotion Drive Interface (SDI) and User-Defined Variable (UDV) Axes do not correctly report the captured position when the axis position has rolled over the data type limit.
615087 SDI Axes can fault when changing move modes SDI Axes can operate in four move modes (homing, velocity, torque, position). While operating in homing, velocity, and torque modes, the position setpoint is not updated in SoftMotion's trajectory generator. When switched back to position mode directly, the position error is calculated as the last known position and the current feedback position. This causes the axis to jump and fault when changing modes.
632971 SDI Axes do not work after SoftMotion is re-initialized SoftMotion Initialization code can be found in KB 75LA9L6R and is needed to clear Scan Engine faults that would otherwise require power cycling the real-time controller. This code cannot be used with SDI Axes due to configuration data that is not reset.
600105 Position move setpoint can jump out of range on move start On multi-core real-time controllers, it is possible for position data to be corrupted before a move is executed. For more information, visit the following site (link to info code NISM2016Q4Notification).
602055 Wait Until Done VI completes execution before move is complete The SoftMotion Wait Until Done VI is used as a blocking function to determine when the current move reference is complete. The Wait Until Done VI does not correctly evaluate the move complete conditions and completes execution before the move is complete.
629856 SoftMotion Straight Line Move does not accept Velocity Setpoint of Zero When using a SoftMotion Straight Line Move in Velocity Mode with an axis resource, commanding a Velocity Setpoint of 0 will not execute.
595072 Position Error resets without being commanded SoftMotion's Position Error parameter is the difference between the position setpoint and position feedback of an axis. This issue affects all axis types and causes the position error to be reset when commanding moves.
601616 VxWorks RT Controllers do not work with SoftMotion Remote Axes NI Real-Time Controllers running the VxWorks OS and SoftMotion do not work with SoftMotion Remote Axes or the Interactive Test Panel. They will function correctly until the target is restarted.
606584 Simulated axes can cause Scan Engine faults if using a low scan period When using Scan Engine periods lower than 5 ms on some targets, SoftMotion simulated axes can cause the Scan Engine to fault.
618627 LabVIEW RT crash when running SoftMotion Axes at high Scan Engine rates Using Scan Engine periods lower than 1ms with SoftMotion may result in a LabVIEW RT crash when running for extended duration. This is caused by a counter rollover which would rollover much slower with slower Scan Engine rates.
600008 SoftMotion Help does not mention 8 UDV axis limit SoftMotion is limited to 8x User-Defined Variable (UDV) SoftMotion Axes per real-time controller. This is currently a limit of the FPGA resources available to SoftMotion. Prior to 2017, this limit was not referenced in the help files.
622802 Read Torque and Read Data (torque) methods have vague documentation These two Read methods for SoftMotion axes appear similar. The documentation has been updated to denote when to use each.
602758 SoftMotion Help contains incorrect description when an axis in a coordinate is stopped In SoftMotion 2015 and newer, the stop behavior of other axes in a Coordinate Space is always set to Decelerate. This change was not reflected in the help files.


Glossary of Terms


  • Bug ID - When an issue is reported to NI, you may be given this ID or find it on  You may also find IDs posted by NI on the discussion forums or in KnowledgeBase articles.
  • Legacy ID – An older issue ID that refers to the same issue.  You may instead find this issue ID in older known issues documents.
  • Description - A few sentences which describe the problem. The brief description given does not necessarily describe the problem in full detail.
  • Workaround - Possible ways to work around the problem.
  • Reported Version - The earliest version in which the issue was reported.
  • Resolved Version - Version in which the issue was resolved or was no longer applicable. "N/A" indicates that the issue has not been resolved.
  • Date Added - The date the issue was added to the document (not the reported date).