CAN Talon / Test Mode Crash

Technical Java
1

Using robot builder, and the latest software from CTRE. If I create a project with a single subsystem, and in that subsystem a single CAN Talon. When the code is deployed, and the robot enabled in test mode we get the following error.

Any ideas on how to resolve this? We do not use test mode a lot, but it does come in very handy when, well testing robots…

Thanks :slight_smile:

<TagVersion>1 <time> 06.899 <count> 1 <flags> 1 <Code> 1 <details> ERROR Unhandled exception: java.lang.NullPointerException: value cannot be null at [edu.wpi.first.wpilibj.networktables.NetworkTablesJNI.putString(Native Method), edu.wpi.first.wpilibj.networktables.NetworkTable.putString(NetworkTable.java:588), edu.wpi.first.wpilibj.livewindow.LiveWindow.initializeLiveWindowComponents(LiveWindow.java:51), edu.wpi.first.wpilibj.livewindow.LiveWindow.setEnabled(LiveWindow.java:74), edu.wpi.first.wpilibj.IterativeRobot.startCompetition(IterativeRobot.java:93), edu.wpi.first.wpilibj.RobotBase.main(RobotBase.java:247)] <location> edu.wpi.first.wpilibj.RobotBase.main(RobotBase.java:249) <stack> 
<TagVersion>1 <time> 06.900 <message> Starting live window mode. 
<TagVersion>1 <time> 06.901 <message> Initializing the components first time 
<TagVersion>1 <time> 06.901 <message> Initializing table for 'Subsystem 1' 'CAN Talon 1' 
<TagVersion>1 <time> 06.902 <message> Error at edu.wpi.first.wpilibj.RobotBase.main(RobotBase.java:249): ERROR Unhandled exception: java.lang.NullPointerException: value cannot be null at [edu.wpi.first.wpilibj.networktables.NetworkTablesJNI.putString(Native Method), edu.wpi.first.wpilibj.networktables.NetworkTable.putString(NetworkTable.java:588), edu.wpi.first.wpilibj.livewindow.LiveWindow.initializeLiveWindowComponents(LiveWindow.java:51), edu.wpi.first.wpilibj.livewindow.LiveWindow.setEnabled(LiveWindow.java:74), edu.wpi.first.wpilibj.IterativeRobot.startCompetition(IterativeRobot.java:93), edu.wpi.first.wpilibj.RobotBase.main(RobotBase.java:247)] 
<TagVersion>1 <time> 06.904 <message> WARNING: Robots don't quit! 
<TagVersion>1 <time> 06.905 <message> ---> The startCompetition() method (or methods called by it) should have handled the exception above.
2

Can you share the main Robot class?

3

Found the problem, we were using CTRE libraries downloaded around kickoff. There was newer libraries on their website. Downloading them, rebuilding, and deploying fixed the problem.

Thanks

FYI we are now using 4.4.1.9

http://www.ctr-electronics.com/hro.html#product_tabs_technical_resources

4