Skip to content

Known Issues VisualApplets Release 3.3.2#


While Update 2301 for VisualApplets 3.3.2 enables using VisualApplets in Windows 11, for some installations of Vivado the build flow may stop after the step Design-Rules-Check-2 with the error message Error: -1 Error checking FPGA software. If you encounter this problem, then modify your build settings so that the precondition check is not activated.


If you install the Windows 10 Fall Creators update (version 1709) on a computer that has Xilinx Vivado version 2017.2 or 2017.3 installed, Xilinx Vivado may not work properly. Thus, you may not be able to build the designs you created with VisualApplets.

Follow the workaround provided by Xilinx Support to make your Xilinx Vivado 2017.2 or 2017.3 installation work again.


If you install the above Windows 10 update, the build flow may not work properly using Xilinx tools older than Vivado 2017.4. Thus, you may not be able to build the designs you created with VisualApplets.

For Vivado versions older than Vivado 2017.4, error messages may show up in the log output of the Xilinx tool chain telling that some black box instances have undefined content. For ISE, no Xilinx tool version can be determined and the FPGA type check fails.

Follow the workaround provided by Xilinx Support to make the ISE installation work again (section "ISE 14.7 64-bit - Turning off SmartHeap"). The same workaround can be used for Vivado where you need to perform the file substitution actions in directory <VivadoInstallDir>/ids_lite/ISE/lib/nt64.


Summary: Tcl Scripts with Color Flavor Values LAB, XYZ, HSL, HSV, or YCrCb Cause Errors During Import
Description: When exporting a design to a Tcl script with Color Flavor values LAB, XYZ, HSL, HSV, or YCrCb in the link properties, importing the design from the script leads to an error.
Workaround: This problem is fixed in VisualApplets 3.4.0. Update your VisualApplets version to 3.4.0
Ticket ID: 258727
Summary: Loading Small Images in TIF Format Leads to Image Magick Error
Description: Loading small images in TIF format sometimes fails with the error message Image Magick library: Image format is not supported. Error code: -70002.
Workaround: In the VisualApplets System Settings, set I/O Image Library to Native, not to Image Magick. Or update your VisualApplets version to 3.4.0.
Ticket ID: 265278
Summary: VisualApplets Sometimes Doesn't Detect a Vivado Version Number
Description: If you build an applet with Vivado 2023.1 or higher, VisualApplets doesn't detect the Vivado version number.
Workaround: Either update your VisualApplets version to 3.4.0 or patch the file vivado.bat in your Vivado installation by inserting the following lines directly after @echo off:
if "%1"=="-version" (
     goto returnVersionInfo

) else (

   goto proceed



echo Vivado v2023.1 (64-bit)
Ticket ID: 285232
Summary: Xilinx ISE Build Toolchain Doesn't Support Windows 11
Description: The Xilinx ISE build toolchain doesn't support Windows 11. Therefore, building VisualApplets designs doesn't work with Xilinx ISE.
Workaround: If you want to build applets for platforms that need to be built with Xilinx ISE, install VisualApplets under Windows 10 or 8.1. If your target platform is supported by Vivado, build the applets with Xilinx Vivado (Vivado supports Windows 11). See in the system requirements which platforms are supported by Vivado.
Ticket ID: 236990
Summary: Applets for mE5-CL Platforms Can't Be Built with some Xilinx Vivado Versions
Description: Applets for mE5-CL platforms can't be built with Vivado versions between 2020.2 and 2021.1.
Workaround: This problem has been fixed with Xilinx Vivado version 2021.2. Thus, to avoid this problem, use Vivado version 2021.2 or higher.
Ticket ID: 217879
Summary: On Windows 8, You Must Define the User Directory as Destination Directory
Description: On Microsoft Windows 8, you must define the user directory as the destination directory. Alternatively, any other directory with full access rights can be used.
Workaround: No workaround is available.
Ticket ID:
Summary: When Converting a Design to a Different Hardware Platform, the Hardware-Dependent Operator Library Might Not Be Available
Description: When converting a VisualApplets design to a different hardware platform, then under certain circumstances the hardware-dependent operator library for the target platform might not be available.
Workaround: To resolve this restart VisualApplets.
Ticket ID:
Summary: You Need to Reset Simulation Conditions After a Simulation Error
Description: After a simulation error has occurred, the simulation conditions need to be reset
Workaround: No workaround is available.
Ticket ID:
Summary: Xilinx Vivado Warning When Building an Applet
Description: When you build an applet using the Xilinx Vivado Tools, you may get critical warnings (in build step LinkDesign). The warnings are due to an issue within the Xilinx tool chain. The issue is known to Xilinx and fixing is in progress. Example:

CRITICAL WARNING: [Shape Builder 18-137] Cannot obey LUTNM/HLUTNM constraint for instances …/PART1174 and …/PART1175. Illegal to place instance …/PART1174 on site SLICE_X2Y0. The location site type does not match the instance type. Instance …/PART1174 belongs to a shape with reference instance …/PART1175. Shape elements have relative placement respect to each other. The invalid location might results from a constraint on any of the instance in the shape..

Workaround: Ignore the warnings. This issue is not critical for designs created in VisualApplets.
Ticket ID:
Summary: Only ASCII Characters Are Supported for *.va File Names
Description: For naming *.va files, only fonts based on ASCII characters can be used; this means that, e.g., Asian, Cyrillic, Greek, or Arabic fonts are not supported for file names.
Workaround: No workaround is available.
Ticket ID:
Summary: Configuration Is Only Saved For First Instance of VisualApplets
Description: Only the first started instance of VisualApplets is able to save its configuration. All VisualApplets instances that have been started later have only a temporary configuration which will be discarded when the instance is closed. This concerns, e.g., build settings, library settings, system settings, general VisualApplets settings.
Workaround: No workaround is available.
Ticket ID:
Summary: Design Rules Check Error When M-Type Operators in a Hierarchical Box Are Connected Directly to the Input Port
Description: If you are using hierarchical boxes, in some specific situations, the Design Rules Check may come up with the following error message: "The input XYZ of the operator ABC (hierarchical box) must be connected to an O-type operator, e.g., NOP." The reason is that some M-type operators placed within a hierarchical box cannot be connected to the input port of the hierarchical box directly. This is only true for some specific M-type operators.
Workaround: You can solve this problem (within the hierarchical box) by placing an NOP operator between the input port of the hierarchical box and the input port of the M-type operator.
Ticket ID:
Summary: Design Rules Check Error When Using the Line-by-Line 1D Simulation Mode
Description: For some designs which passed the Design Rules Check in former versions of VisualApplets, link errors concerning the max. image height may be reported. In particular this may happen when 1D processing is involved and the new line-by-line simulation mode is activated (default). The reason is that in the line-by-line-mode some operators propagate the max. image height of input links in a different way to the output links than before.
Workaround: You can solve this problem by changing to the legacy simulation mode or by adding SetDimension modules for adjusting the max. image height values.
Ticket ID:
Summary: Increased Operating Time When Using the Line-by-Line 1D Simulation Mode
Description: For some designs the operating time for simulation may be much higher than in former versions of VisualApplets. In particular this may happen when 1D processing is involved, the new line-by-line simulation mode is activated (default), and the design contains many simulation probes.
Workaround: You can solve this problem by changing to the legacy simulation mode or by reducing the number of simulation probes.
Ticket ID:
Summary: SDK for CXP: Access to the SISO_GenICam Library Have to Be Programmed by the User
Description: SDK for CXP: Accesses to the SISO_GenICam library are not generated automatically, but have to be programmed by the user.
Workaround: No workaround is available.
Ticket ID:
Summary: Increasing the FPGA Design Clock Frequency May Lead to Slow Builds
Description: Increasing the FPGA design clock frequency may have the result that the build flow takes very long or even fails because timing constraints cannot be met. This strongly depends on the content of the VisualApplets design.
Workaround: No workaround is available.
Ticket ID: 8513
Summary: Large Images Are Not Displayed in Simulation Probes
Description: When simulation probes contain very large images, VisualApplets may fail to display these images correctly due to memory limitations. In that case, a gray image (i.e. all pixels have the value 205 (0xCD)) is shown.
Workaround: Use smaller images for simulation.
Ticket ID: 6822
Summary: Simulation Only Supports Images Smaller than 2 GB
Description: During simulation the internal buffer size for any image is limited to 2 GB. Simulations with an image that is larger than 2 GB, the simulation is stopped with an error message.
Workaround: Use images smaller than 2 GB for simulation.
Ticket ID: 240989

Library Blob#

Operator Blob_Analysis_1D#

Summary: The Operator Blob_Analysis_1D Sets the Flag object size exceeds maximum Not as Expected
Description: If an object is truncated due to exceeding the maximum size defined by parameter max_object_height_bits, the corresponding flag object size exceeds maximum is set in the truncated object and not in the proceeding object.
Workaround: No workaround is available.
Ticket ID: 9685
Summary: The Operator Blob_Analysis_1D Does Not Set the Flag label overflow
Description: The flag label overflow indicating that all labels are in use and the current object cannot be tagged, is never set.
Workaround: No workaround is available.
Ticket ID: 9691
Summary: The Operator Blob_Analysis_1D Allows 20 Labels Less Than Defined per Line
Description: The amount of available labels as defined via the parameter Label_bits is reduced by 20 labels. For example, if Label_bits is set to 5, only 12 (2^5 - 20) labels are available, and not 32 as expected (2^5).
Workaround: No workaround is available.
Ticket ID: 9688
Summary: The Simulation of The Operator Blob_Analysis_1D is Not Equal to Hardware Behavior
Description: The order of the object feature output might differ in hardware and software. This is so, because the hardware output depends on the timing of the data which cannot be simulated in VisualApplets. Additionally, the FlushI input is asynchronous to the image data input, so completing output frames may not be simulated in a realistic way.
Workaround: No workaround is available.
Ticket ID: 7709

Library Color#

Summary: Some Color Conversions Don't Work As Expected
Description: Operators of the Color library should be used carefully: Some color conversions don't work as a user would assume:
  • HSI2RGB converts HSL -> RGB ,
  • RGB2YUV converts RGB->YCbCr,
  • XYZ2LAB uses constants according to the following definitions:
Workaround: No workaround is available.
Ticket ID:

Operator ColorTransform#

Summary: Limitations for Negative Transformations Coefficients
Description: Operator ColorTransform supports negative transformation coefficients only for the case when the input format is signed or the coefficients are static.
Workaround: No workaround is available.
Ticket ID: 251344

Operator BAYER5x5Linear#

Summary: The Resource Estimation in VisualApplets for BAYER5x5Linear Differs From the Estimation in Xilinx
Description: BAYER5x5Linear: In some cases, the resource estimation in VisualApplets for this operator (in dialog FPGA Resource Usage) might differ from the estimation displayed by the Xilinx tools after Place & Route.
Workaround: No workaround is available.
Ticket ID: 6426

Library Compression#

Operator JPEG_Encoder#

Summary: The Output Transfer Of the Operator JPEG_Encoder Starts Earlier Than the Actual Image Data Transfer
Description: Operator : To optimize its image throughput rate (band width), the operator outputs the header as soon as header generation is activated - even before image data arrive at the operator's input. This way, the transfer of the header data doesn't interrupt the transfer of image data, as the header is transferred in advance. The drawback of this practice is that the operator's output transfer starts earlier than the actual image data transfer. This may cause irritations under specific circumstances:
If you are using the operator SourceSelector directly after JPEG_Encoder: Operator SourceSelector registers a partly processed frame as soon as it gets the header data. Therefore, if SourceSelector is switched to getting image data from JPEG_Encoder, SourceSelector cannot be switched to any another source as it always detects an unfinished frame. In addition, when header generation is enabled and SourceSelector switches from another source to the JPEG_Encoder channel, the first image is lost.
Workaround: If working on eVA devices, make sure the output is capable to accept data transfer before the sensor transfer is started.
Ticket ID:

Library Debugging#

Operator ImageFlowControl#

Summary: Damaged Frame After an Overflow Situation
Description: Using the operator ImageFlowControl in dummy frame generation mode may result in a damaged frame as output. This happens after an overflow situation, when a series of dummy frames is emitted for compensating lost frames.
Workaround: No workaround is available.
Ticket ID: 248227

Library Filter#

Operator FIRKernelNxM#

Summary: Operator FIRKernelNxM May Cause Processing Errors
Description: The operator FIRKernelNxM may cause processing errors in case parameter EdgeHandling is set to constant, the number of columns > 2*parallelism, the number of kernel columns is an even number, and parallelism > 1. The error can be monitored at the left border of an image, where wrong pixel data is used at the kernel positions inside the frame.
Workaround: No workaround is available.
Ticket ID: 2939

Library Hardware Platforms#

Trigger Operators#

Summary: Trigger Operators May Cause Spikes at the Trigger Output Line
Description: Trigger operators may cause spikes at the trigger output line during initialization phase when loading the applet onto the frame grabber.
Workaround: No workaround is available.
Ticket ID:

Library Memory#

Operator ImageBufferMultiRoiDyn#

Summary: Timing Errors with Small Images
Description: The operator ImageBufferMultiRoiDyn may cause timing errors in case of very small input images.
Workaround: No workaround is available.
Ticket ID:

Operator ImageSequence#

Summary: Build Errors Caused by the Operator ImageSequence
Description: The operator ImageSequence may cause build errors (timing errors).
Workaround: No workaround is available.
Ticket ID: 2422