FlexRIO 21.3 Known Issues

Overview

This document contains the FlexRIO known issues that were discovered before and since the release of FlexRIO 21.3. Known issues are performance issues or technical bugs that NI has acknowledged exist within this version of the product.

 

Not every issue known to NI appears on this list; it is intended to show the most severe and common issues that you may encounter and provide workarounds when possible. Other technical issues that you may encounter could occur through normal product use or system compatibility issues. You may find more information on these issues in NI’s Product Documentation, Knowledgebase, or Community.

Bug Number

Legacy ID

Description

Details

230875 596974

When synchronizing multiple NI 5752 or NI 5752B FlexRIO Adapter Modules there may be one sample of uncertainty.

Due to a known issue in the constraints of the CLIPs for the NI 5752 and 5752B FlexRIO Adapter Modules there may be one sample of uncertainty when attempting to send the AdcTgcStart signal to the ADCs on the adapter modules. This may cause the gain sweep to start at different samples between adapter modules.

Workaround:

There is currently no known workaround for this issue.

Reported Version:

FlexRIO 16.0

Resolved Version:

N/A

Added:

N/A

883400 545599

The Controller for FlexRIO (NI-793XR) does not support debugging FPGA VIs using a third-party simulator.

The Controller for FlexRIO (NI-793XR) does not support the use of a third-party simulator to simulate and debug a LabVIEW FPGA VI.

Workaround:

There is currently no known workaround for this issue.

Reported Version:

FlexRIO 16.0 | NI-793xR 15.1

Resolved Version:

N/A

Added:

N/A

891271 554346

The Aurora CLIP shipped with the NI-793xR - MGT Aurora CLIP example may fail to initialize.

A design using the Aurora CLIP from the NI-793xR - MGT Aurora CLIP example project may fail to initialize after downloading a bitfile or resetting the FPGA.

Workaround:

Use the status signals on the Aurora CLIP to determine if an error occurred and re-download the bitfile until the CLIP initializes without an error.

Reported Version:

FlexRIO 16.0

Resolved Version:

N/A

Added:

N/A

889041 555601

DRAM on NI PXIe-797xR FlexRIO FPGA Modules is inaccessible immediately after a download or reset of the FPGA.

DRAM on NI PXIe-797xR FlexRIO FPGA Modules is inaccessible immediately after a download or reset of the FPGA. A wait of at least 2.5 seconds must be added before before accessing the DRAM after an FPGA download or reset.

Workaround:

After any reset or download of the FPGA, wait at least 2.5 seconds before accessing the DRAM.

Reported Version:

FlexRIO 16.0 | PXIe-797xR 15.0

Resolved Version:

N/A

Added:

N/A

531101 526736

In the Streaming instrument design library, Wait For Stream.vi can return an incorrect value for the Samples Transferred output when an FPGA target is executed in simulation mode.

In the Streaming instrument design library, due to a race condition present only in simulation mode, Wait For Stream.vi can return the second to last Samples Transferred value rather than the expected terminal value of a finite transfer.

Workaround:

Do not use the Samples Transferred output from Wait For Stream.vi as the value for the Requested Elements input on a DMA FIFO when completing a finite transfer.

Reported Version:

FlexRIO 14.0

Resolved Version:

N/A

Added:

N/A

531617 624455

In the "NI 5783 - Getting Started" example, Data Clock setting is 125 MHz single frequency, which is inconsistent with x2 Data Clock (200 MHz).

In the "NI 5783 - Getting Started" example, Data Clock setting is 125 MHz single frequency, which is inconsistent with x2 Data Clock (200 MHz). This inconsistency leads to a compilation error for certain IPs that require Data Clock and x2 Data Clock for overclocking. The error notes that the frequency is not within the requested range for the target.

Workaround:

Reload NI 5783 CLIP by disabling NI 5783 FAM and re-enabling NI 5783 FAM.

Reported Version:

FlexRIO 16.1

Resolved Version:

N/A

Added:

N/A

531516 722379

Premature overflow of dynamically arbitrated DRAM FIFO

When the DRAM FIFO process VI is set to "dynamic (priority writes)" and the "from DRAM" queue is full there is a chance that the FIFO prematurely overflows.

Workaround:

Set the dynamic arbitration setting to "none" and use the "read grant time" and "write grant time" to arbitrate throughput.

Reported Version:

FlexRIO 18.6

Resolved Version:

N/A

Added:

N/A

1042857

Estimated timing and final timing are grayed out in the Compilation window for the NI-7935

After a successful FPGA compilation for a NI-7935, the Estimated timing and Final timing tabs in the FPGA Compilation Status window are grayed out and not selectable.

Workaround:

The FPGA compilation would fail if the desired timing constraints are not met. A successful compilation means your timing constraints were met. To manually verify successful compilation for clock timing constraints, you can check the FPGA compilation output XML file. The Route_Twx section will list PASS for clocks listed that successfully meet the timing constraints. The XML file is located here: C:\NIFPGA\compilation\\output_files.zip\lvParsedReports.xml

Reported Version:

FlexRIO 18.7

Resolved Version:

N/A

Added:

Jan 8, 2021

Final Time Issue Listed

Issues found in this section will not be listed in future known issues documents for this product.

There are currently no issues to list.

Additional Resources

Explore Support Content and Product Documentation 

 

 

Ask the NI Community

 

 

Request Support from an Engineer

 

A valid service agreement may be required, and support options vary by country

 

Glossary of Terms

 

  • Bug ID - When an issue is reported to NI, you may be given this ID or find it on ni.com.  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).