NI does not actively maintain this document.
This content provides support for older products and technology, so you may notice outdated links or obsolete information about operating systems or other relevant products.
The following items are known issues in the LabVIEW 8.6 Control Design and Simulation Module.
| ID | Known Issue |
| 103270 | Crash when deploying to NI CompactRIO device using RT desktop target LabVIEW might crash when you deploy a simulation to a NI CompactRIO device using an RT desktop target. The RT desktop target is not intended for use with CompactRIO devices. If you want to deploy a simulation to a CompactRIO device, use the appropriate RT CompactRIO target. |
| 100760 | Mass compile simulation subsystems or Simulation Loops in build specifications If you want to use a simulation subsystem or VI containing a Simulation Loop as a source file in a build specification, you first must mass compile or save the subsystem or VI in the current version of LabVIEW. |
| 115644 | Not all Microprocessor SKD example targets supported You can use the Control Design and Simulation Module with only the following Microprocessor SDK example targets:
|
| VIs and Functions | |
| — | Some VIs appear broken after mass compilation If you mass compile the labview\vi.lib\addons\Control Design directory, the following VIs appear broken: CD Discrete State-Space, CD Discrete Stochastic State-Space (External), CD Discrete Stochastic State-Space (Internal), CD Discrete Transfer Function, CD Discrete Zero-Pole-Gain, CD Predictive Observer, cd_Design PID for Discrete Systems (ZPK), CD Design PID for Discrete Systems, cd_Design PID for Discrete Systems (SS), CD Discrete State-space, CD Bode Graph, CD Nichols Graph, CD Nyquist Graph, CD Pole-Zero Map Graph, CD Root Locus Graph, CD Time Domain Simulation, CD SxZExternInnards. These VIs are not actually broken. |
| 114491 | Discrete Linear Systems functions ignore skew parameter The Discrete State-Space function, Discrete Transfer Function function, and Discrete Zero-Pole-Gain function ignore the skew parameter if you select Configuration Dialog Box from the Parameter source pull-down menu. Select Terminal from the Parameter source pull-down menu and wire a control to the skew terminal on the block diagram to modify the skew value. |
| 39212 | CD Canonical State-Space Realization VI does not support MIMO system models The CD Canonical State-Space Realization VI works only with single-input single-output (SISO) system models. Therefore, if you wire a multiple-input multiple-output (MIMO) system model to this VI, the VI recognizes only the first (0th) element of this system model. Workaround—Use the Array functions to index a MIMO system manually and send each element to this VI. |
| — | Display issues on Windows Vista If you install the Control Design and Simulation Module on Microsoft Windows Vista and use a 120 DPI font setting, the configuration dialog boxes of the Simulation functions look incorrect. The front panels of some example VIs also look incorrect. Workaround—These functions and VIs are not broken. However, you can use a different DPI setting to adjust the appearance. |
| 49715 | Creating subsystem from VI template results in broken VI Creating a new simulation subsystem from a subsystem VI template results in a broken VI. Workaround—Edit the VI and then recompile the VI. Compiling occurs when you create, save, or load a VI, and also at other times. |
| — | Express VIs on simulation diagram display incorrect font Express VIs on the simulation diagram display execution status using the incorrect font size. |
| 51203 | VI executes extra minor time step If you set up a VI to execute continuously with minor time steps, the VI executes an additional time after the last major time step. |
| 49285 | Compiling subsystem erases clipboard Compiling a simulation subsystem erases the contents of the Windows clipboard. |
| — | Error reporting inconsistent based on feedthrough Error reporting behaves differently depending on whether a function has direct or indirect feedthrough. |
| — | Improper feedthrough behavior inside Conditional Disable structure Placing a Simulation function inside a Conditional Disable structure might cause the feedthrough behavior to work improperly. |
| — | Run button appears broken after recreating wire Deleting and then recreating a wire might cause the Run button to appear broken. Workaround—Click the Run button to run the VI. |
| — | VIs containing discrete Simulation functions appear broken VIs that contain a discrete Simulation function and are saved in a previous version of the Simulation Module appear broken. Workaround—Click the Run button to run the VI. |
| — | Build specifications fail Build specifications fail unless all VIs are saved in the current version of LabVIEW. |
| — | Wires exiting Simulation Loop appear broken Wires exiting the Simulation Loop might appear broken when you save or compile a VI. Workaround—Move the mouse cursor over the wire. |
| 48302 | Broken Save and Load buttons If you open the configuration dialog box of the State-Space, Transfer Function, Zero-Pole-Gain, Lookup Table 1D, or Lookup Table 2D functions and click the Cancel button, the Save and Load buttons might not work the next time you open the dialog box. |
| — | Sample skew parameter mishandles non-zero values The sample skew parameter of the Discrete Linear Systems functions does not properly handle non-zero values. If you specify a non-zero sample skew value for a function, that function might have incorrect output for times between the initial simulation time and the time you specified for execution. |
| — | RT Communication Wizard does not work with stand-alone subsystems The RT Communication Wizard does not work with stand-alone Simulation subsystems. |
| 88068 | Cannot undo changes in discrete rates You cannot undo or redo changes in subVI discrete rates. |
| — | Resizing Simulation functions do not constrain icon proportions Holding the <Shift> or <Ctrl> keys while resizing Simulation function icons does not constrain the proportions of the icon. |
| — | LabVIEW deletes undo information when creating a subsystem Creating a simulation subsystem from a portion of a VI block diagram causes LabVIEW to delete all undo information. To undo creating the subsystem, you can copy the subsystem block diagram code, delete the subsystem icon from the VI block diagram, and paste the code back onto the VI block diagram. |
| — | Some instances of the Discrete Kalman Filter and Discrete Observer functions do not support deterministic real-time execution If you specify Indirect feedthrough and the No Corr, w/ Check, No Corr, w/o Check, No Pred Gain, w/ Check, or Pred Gain, w/ Check instance, the Discrete Kalman Filter function does not support deterministic real-time execution. If you specify Indirect feedthrough and the Current Observer, w/ Check or Predictive Observer, w/ Check instance, the Discrete Observer function does not support deterministic real-time execution. |
| Simulation Model Converter | |
| — | Closing Simulation Model Converter returns error After you close the Simulation Model Converter, the MATLAB® application software might display the following message: " Cannot close the model '<ModelName>' when it is being compiled or while the simulation is running". In this situation, enter the following command in the MATLAB® application software: <ModelName> ([],[],[],'term'), where <ModelName> is the name of the model you converted. |
| 35496 | Digital Clock block converts to continuous function The Digital Clock block converts to the Get Simulation Time function, which executes continuously. |
| 38076 | Signals from S-Function block convert to vectors Signals from the S-Function block always convert to a vector data type. |
| — | Must convert data types after model conversion After you use convert a model, you might need to convert some data types. To convert from a double to a Boolean, insert a Not Equal to Zero? block. To convert from a Boolean to a double, insert a Boolean to (0, 1) block. |
| — | Currently Converting indicator includes time that Errors and Warnings dialog box is open If you place a checkmark in the Show Errors checkbox and convert a model, the Currently Converting indicator includes the time for which you keep the Errors and Warnings dialog box open. If you do not want to include this time, place a checkmark in the Log Errors checkbox instead of the Show Errors checkbox. |
| — | Array indexes in converted models misaligned Array indexes in array assignment and selector nodes might be off by one, because LabVIEW array indexes are zero-based. |
| — | Fcn block converts to MATLAB script node The Fcn block converts to the MATLAB script node with only scalar double input terms. |
| 37678 | Product blocks in Matrix Multiply mode do not function correctly Product blocks in Matrix Multiply mode do not function correctly. Try replacing the Product block with the A x B VI. |
| — | Scope block with multiple input signals only has first input connected If the model you want to convert contains a Scope block with multiple input signals, the Simulation Model Converter connects only the first input to that block. |
| — | View button might not highlight corresponding node The View button in the Errors and Warnings window might not highlight a corresponding node. |
| 115677 | (Linux) Cannot convert models containing Manual Switch block You cannot convert models that contain a Manual Switch block. |
| Control Design MathScript Functions | |
| — | LabVIEW MathScript functions take time to display results Some LabVIEW MathScript functions display results in an external window. The first external window to appear takes a considerably longer time to display than subsequent windows. |
| 89687 | Cannot make root locus plots part of subplots You cannot make root locus plots part of subplots. |
| — | Transfer function polynomial coefficients listed in descending order In the LabVIEW MathScript environment, transfer function polynomial coefficients always are in descending order. However, the Control Design VIs assume these coefficients are in ascending order. |
| Documentation | |
| 116020 | Place and Find buttons broken for Implementation VIs and functions In the LabVIEW Help, the Place on the block diagram and Find on the Functions palette buttons do not work for the Implementation VIs and functions. |
MATLAB® is the registered trademark of The MathWorks, Inc.