בעיות ידעות

This article details known issues (and workarounds) for FRC® Control System Software.

בעיות פתוחות

Visual Studio Code extensions fail to install on macOS

Issue: With macOS Monterrey 12.3 or later, the VS Code extensions do not install automatically. This is due to the fact that macOS 12.3 removed python, but VS Code 1.62 installed by the WPILib Installer uses python when loading extensions.

Workaround: Manually install the VS Code extensions

  1. Go to VS Code extensions (1), then three dots (2), then Install from VSIX (3).

  2. Navigate to ~/wpilib/2022/vsCodeExtensions and install CPP.vsix

  3. Repeat for the remaining 4 extensions (JavaDebug.vsix, JavaDeps.vsix, JavaLang.vsix, WPILib.vsix)

  4. Restart VS Code.

VS Code screen showing the navigation steps to Install from VSIX

Onboard I2C Causing System Lockups

Issue: Use of the onboard I2C port, in any language, can result in system lockups. The frequency of these lockups appears to be dependent on the specific hardware (i.e. different roboRIOs will behave differently) as well as how the bus is being used.

Workaround: The only surefire mitigation is to use the MXP I2C port or another device to read the I2C data. Acessing the device less frequently and/or using a different roboRIO may significantly reduce the likelihood/frequency of lockups, it will be up to each team to assess their tolerance of the risk of lockup. This lockup can not be definitively identified on the field and a field fault will not be called for a match where this behavior is believed to occur. This lockup is a CPU/kernel hang, the roboRIO will completely stop responding and will not be accessible via the DS, webpage or SSH. If you can access your roboRIO via any of these methods, you are experiencing a different issue.

Several alternatives exist for accessing the REV color sensor without using the roboRIO I2C port. A similar approach could be used for other I2C sensors.

  • Use a Raspberry Pi Pico. Supports up to 2 REV color sensors, sends data to the roboRIO via serial. The Pi Pico is low cost (less than $10) and readily available.

  • Use a Raspberry Pi. Supports 1-4 color sensors, sends data to the roboRIO via NetworkTables. Primarily useful for teams already using a Raspberry Pi as a coprocessor.

CAN bus utilization is noisy

Issue: CAN bus utilization as reported live by the DS or as shown in the DS log has significant variation or ”spikes“ in the data. This is due to the RoboRIO occasionally counting CAN packets in the incorrect time period, so one period will have a much lower utilization than reality and the next a much higher utilization than reality.

Workaround: Zoom in on the DS log plot and look for time periods when the utilization is stable (the spikes will be both above and below this average). The average utilization is the true utilization.

Updating Properties on roboRIO 2.0 may be slow or hang

Issue: Updating the properties on a roboRIO 2.0 without reformatting using the Imaging Tool (such as setting the team number) may be slow or hang.

Workaround: After a few minutes of the tool waiting the roboRIO should be able to be rebooted and the new properties should be set.

Simulation crashes on Mac after updating WPILib

Issue: On macOS, after updating the project to use a newer version of WPILib, running simulation immediately crashes without the GUI appearing.

Workaround: In VS Code, run WPILib | Run a command in Gradle, clean. Alternatively, run ./gradlew clean in the terminal or delete the build directory.

Invalid build due to missing GradleRIO

Issue: Rarely, a user’s Gradle cache will get broken and they will get shown errors similar to the following:

Could not apply requested plugin [id: ‘edu.wpi.first.GradleRIO’, version: ‘2020.3.2’] as it does not provide a plugin with id ‘edu.wpi.first.GradleRIO’


Delete your Gradle cache located under ~$USER_HOME/.gradle. Windows machines may need to enable the ability to view hidden files. This issue has only shown up on Windows so far. Please report this issue if you get it on an alternative OS.

Unable to Build Robot Projects outside of VS Code on M1-based macOS

Issue: Error when building a robot project in non-WPILib installations.

Could not determine the dependencies of task ':extractReleaseNative'.
> Could not resolve all files for configuration ':nativeRelease'.
  > Failed to transform hal-cpp-2022.1.1-rc-1-osxx86.zip (edu.wpi.first.hal:hal-cpp:2022.1.1-rc-1) to match attributes {artifactType=gr-directory, org.gradle.status=release}.

Workaround: M1-based macOS is not supported. The above error will show up when using an ARM-based JDK. User must use a x64-compatible JDK 11 or preferably use the WPILib installer.

תווים סיניים ב-Driver Station Log

בעיה: לעיתים נדירות, ה-Log של ה-Driver Station מציג תווים סיניים במקום הטקסט באנגלית. נראה שזה קורה רק כאשר Windows מוגדר לשפה שאינה אנגלית.

Chinese character appearing in the Driver Station log window.

עקיפת הבעיה: ישנם 2 דרכים ידועות לעקיפת הבעיה:

  1. העתיקו והדביקו את התווים הסיניים אל Notepad, והטקסט באנגלית יוצג.

  2. שנו באופן זמני את את שפת ה-Windows לאנגלית.

C++ Intellisense - Files Open on Launch Don’t Work Properly

Issue: In C++, files open when VS Code launches will have issues with Intellisense showing suggestions from all options from a compilation unit and not just the appropriate ones or not finding header files. This is a bug in VS Code.


  1. Close all files in VS Code, but leave VS Code open

  2. Delete c_cpp_properties.json file in the .vscode folder, if it exists

  3. Run the ”Refresh C++ Intellisense“ command in VS Code.

  4. In the bottom right you should see something that looks like a platform (linuxathena or windowsx86-64 etc). If it’s not linuxathena click it and set it to linuxathena (release)

  5. Wait ~1 min

  6. Open the main cpp file (not a header file). Intellisense should now be working

Issues with WPILib Dashboards and Simulation on Windows N Editions

Issue: WPILib code using CSCore (dashboards and simulated robot code) will have issues on Education N editions of Windows.

  • Shuffleboard will run, but not load cameras

  • Smartdashbard will crash on start-up

  • Robot Simulation will crash on start-up

Solution: Install the Media Feature Pack

NetworkTables Interoperability

There is currently an issue with inter-operating C++/Java NetworkTables clients (dashboards or co-processors) with LabVIEW servers (LV robot code). In some scenarios users will see updates from one client fail to be replicated across to other clients (e.g. data from a co-processor will not be properly replicated out to a dashboard). Data still continues to return correctly when accessed by code on the server.

Workaround: Write code on the server to mirror any keys you wish to see on other clients (e.g. dashboards) to a separate key. For example, if you have a key named targetX being published by a co-processor that you want to show up on a dashboard, you could write code on the robot to read the key and re-write it to a key like targetXDash.

LabVIEW Autorun graphics say 2020

LabVIEW autorun screen showing mismatched versions

Issue: If you launch the LabVIEW installer by using the Autorun file, the menu item correctly says 2022, but the graphic says 2020.

Workaround: This can be safely ignored, if the menu item says 2022, you are installing the correct software.

Fixed in WPILib 2022.4.1

Reentrant uses of synchronized may cause deadlock in Java

Issue: If multiple threads call a synchronized object, there may be a deadlock. This is caused by a bug in the version of JDK bundled with the 2022.1.1 to 2022.3.1 versions of WPILib.

The old commands framework, when using PIDController and PIDCommand, is possibly susceptible to this issue. If using that combination, please update to the latest WPILib to solve the issue.

Workaround: There are two options for workarounds:

  1. Install the 2021 JDK. This is performed automatically in WPILib 2022.4.1 and later.

    1. Download the 2021 JDK.

    2. Copy the downloaded .ipk file to the roboRIO.

    3. SSH as admin to the roborio and execute opkg remove frc2022-openjdk* and opkg install roborio-2021-11.0.9u11-1.ipk

  2. Replace uses of synchronized with reentrantLock

try {
  ...do code here...
} finally {

ADIS16448 not reading values in Java

Issue: In WPILib 2022.3.1, using the no-args constructor for the ADIS16448 IMU in Java results in an divide by zero exception in a separate thread and no IMU data updates.

Workaround: Instead of the no-args constructor, use new ADIS16448_IMU(ADIS16448_IMU.IMUAxis.kZ, SPI.Port.kMXP, ADIS16448_IMU.CalibrationTime._1s);.

Fixed in Image 2022_v4.0 (Game Tools 2022 f1 and WPILib 2022.3.1)

Analog Devices Gyros don’t work properly

Issue: Due to an issue with the ”autoSPI“ feature in the roboRIO image 2022_v3.0, Analog Devices gyros do not work properly.

Workaround: There is no known workaround. An updated image will be released when the issue has been resolved.

Fixed in WPILib 2022.2.1

Joysticks may stop updating in Java

Issue: A deadlock in the Java WPILib DriverStation thread may occur. This is primarily noticeable by Joystick values ”freezing“ and not updating. Disable and E-Stop are not affected by this issue.

Recommendations: Ensure that anyone operating a robot is prepared to disable or E-Stop if this issue occurs. Limit calls to the following DriverStation methods: isEnabled, isEStopped, isAutonomous, isDisabled, isAutonomousEnabled, isTeleopEnabled, isTest, isDSAttached, isFMSAttached, and updateControlWord, especially from multiple threads, to limit the chance of the deadlock occurring. Follow this WPILib issue for more updates and possible workarounds.

VS Code Vendor Check for Updates Broken

Issue: Checking for vendor library updates online results in the following error message: Command »WPILib: Manage Vendor Libraries« resulted in an error (Only absolute URLs are supported). This is caused by a bug in the VS Code extension related to the way the WPILib Command library vendordeps were created. This issue will be fixed in the next WPILib release.

Workaround: If you aren’t using either the new or old Command vendordep, remove them from your project. Alternately, the new or old Command vendordep can be temporarily removed before checking for updates, and then re-added.

Shuffleboard aborts while launching

Issue: Shuffleboard may start to open, and then abort. This is caused by issues with the scripts for launching the WPILib tools.

Workaround: Manually launch Shuffleboard from the commandline without using the shortcut or script. On Windows run c:\Users\Public\wpilib\2022\jdk\bin\java -jar c:\Users\Public\wpilib\2022\tools\shuffleboard.jar. On Linux or macOS, run ~/wpilib/2022/jdk/bin/java -jar ~/wpilib/2022/tools/shuffleboard.jar


This issue may affect any WPILib Java tool, as they use the same scripts to open. If you have issues with PathWeaver, RobotBuilder, or SmartDashboard replace shuffleboard.jar above with PathWeaver.jar, RobotBuilder.jar or SmartDashboard.jar