Driver Station Freezing

Our driver station is often freezing when we connect to the field, and we were wondering if any teams had experienced similar issues or found solutions. It’s causing an issue with our joysticks.

The first time it happened, the driver station froze as soon as it connected to the FMS. I could click on the tabs on the left, but the driver station did not change tabs. The battery voltage display was still changing, so we still had a connection with the robot. When the practice match started, our robot did not enable, but we knew we still had connection with the robot because we could see the battery voltage change.

After using the task manager to close the DS and opening it again, we could see that we had connected to the robot, but we had no connection with the FMS. The FTA was very confused as to how we could be plugged into the field, reading sensors from our robot, and had the option to enable the robot, but we did not see FMS connected on the DS, and the FMS did not see either the robot or the laptop.

We’ve had more freezes of the DS while playing competition matches, but the robot still enabled and we could control it. Interestingly, the SmartDashboard stops working when the DS freezes.

The big problem is that when the DS is frozen, we can’t switch our joysticks if they come up in the wrong order, which happens from time to time, and we won’t be able to drive the robot. Closing and opening the driver station application doesn’t solve the problem either.

The DS UI freeze happens when a synchronous operation inside of an event structure takes much longer than expected, thus blocking the processing of other button clicks and such. Pretty much all of the communication and protocol work takes place in independent/parallel loops that should be unaffected.

The DS released 12/14 experienced this when mDNS was unexpectedly affected by firewall or other protective SW. An operation that normally took 200ms was taking many seconds. So the DS release in 2/15 moved the mDNS call out of the event structure so that a slow return wouldn’t affect other UI events. It also printed a message when the slow return is detected.

Apparently, you have discovered something similar. I have never reproduced this or seen it happen at an event, so I don’t have good info for debugging it.

Do you think that a particular tab or button or operation is common to when you see it freeze? Does it happen at about the same time as the communications light comes on?

Thanks for any helpful debugging info.
Greg McKaskle

Congrats on going to champs!

This is almost certainly something about the configuration of your driver station machine. I personally started the DS software about 500 times on team DS machines connected to the field this year and never saw your problem.

Here’s some ideas for you that will both help Greg find the issue and make sure you have a good experience.

  1. Before starting, run msinfo32 and export your configuration into a text file on the local disk, naming it something like “before.txt”

  2. Remove all other installed software on the DS machine. No Spotify, CAD software, IDEs, games, game VPN software, iTunes, toolbars, etc. You can keep OEM software like video control panels.

  3. Now run msinfo32 again and export. This time name it “after.txt”

  4. Make a backup driver station machine. If I was in your situation, this machine would have a fresh Windows 8.1 install, fully up to date on patches (keep running Windows Update until no changes are proposed), with Windows Firewall turned off. Install only what’s needed to get the DS software installed.

  5. When you arrive at champs, go find a CSA, explain the connection problem you have, and ask them to go with you to the FTA to see if you can validate your connection before practice starts. Depending on the FTA, they may want to try to resolve your issue prior to practice starting. Try both the primary DS and the backup.

If removing the software solved the problem on your primary laptop, Greg will be particularly interested in the before and after msinfo32 exports.

It happened twice today in all of our matches. We never had the failure where we could enable our robot while connected. I’ve noticed that many other teams are having weird issues with long connection times on the field at NE district champs, and we usually have to restart the driver station and change our team number to another number and back before we can connect to the field.

Restarting the driver station does not stop the driver station from freezing, but if I log out/log in, the driver station will work normally.

We also see an error message when tethering which says “The mDNS service is slow to respond”. The same error came up on the old laptop all the time, but we never experienced the freeze.

The laptop that had this issue has no extra software on it at all. It’s an hp 350 g1 laptop that is brand new, and I uninstalled skype, evernote, and a DVD player application. I also removed all antivirus software and disabled the firewall. I’ll be able to give the msinfo32 data in a few days.

The freeze has only happened after we connect to the robot through the field and when I click on the third tab down on the left (the gear, IIRC).

And if a hands-on demonstration is in order, I’ll be in the NI support booth. It will look a bit like CSA central.

Greg McKaskle

What you describe here is pretty normal for 2015. For teams with otherwise working DS/Robot combos, it was a pain but not a blocker.

Just for completeness – what version of the Driver Station are you using?

These two approaches to getting the DS to connect to the field work because they re-initiate the mDNS process. Another way to do this is to disable then re-enable the NIC.

I hope FIRST adds a simple button to the next version of DS that will manually re-initiate the mDNS service. It would save several minutes a day.

I don’t have the laptop with me to check, but I downloaded the update from the NI website on 4/6/2015.

I’m not sure about the FMS issue, but our DS freezes occasionally too. We worked out that the dashboard was malfunctioning and taking up all of our RAM and CPU resources. After killing the process in Task Mananger, the DS started working again. You might want to check if that’s what is going on with yours.

The Offseason Driver Station Update resolves at least one freezing issue, as well as several other issues.

Thanks for the Heads Up Joe!

And we can now view our pdp logs!!