T4.1 deep freeze

[Fenichel]

I have a stable app running on a Teensy 4.1. After more than a week of uninterrupted operation (not connected to any USB port), the Teensy froze, and power cycling did not revive it. When I reconnected it to my computer (Windows 7/64) and tried to reload it from the Arduino IDE (2.1.1, CLI 0.32.3), its USB port (Raw HID) was invisible to the IDE. Restarting Windows (not a total reboot) didn't help. After a reboot of Windows, the Teensy was visible, and it was running its default Blink program. I was able to reload my code without incident, and now it is again running as it was ten days ago.

This failure mode is new to me; I don't know how I'd get it to occur if I wanted it to.

I'll be happy to post all my code here (~ 2K lines), but possibly another member has had a similar experience and can suggest where I should look.

 

[PaulStoffregen]

Please consider updating to at least Window 10.

Windows 7 and 8 (and Vista, XP) have USB driver bugs which can appear as if Teensy (and other types of USB devices) aren't working, when in fact the driver got messed up because of bad leftover state in the Windows Registry. Almost impossible to know whether you're seeing actual trouble with Teensy, or if it's just unreliable Windows USB drivers.

Microsoft finally fixed these really unfortunate problems with Windows 10. But they never back-ported the fixes as updates for Windows 7 or Windows 8.

Please do your sanity a huge favor and use at least Windows 10 (or Linux or MacOS) so you're not running on an old Windows where USB would usually work but occasionally suffer from really confusing problems.

 

[Fenichel]

Please consider updating to at least Window 10.

Windows 7 and 8 (and Vista, XP) have USB driver bugs which can appear as if Teensy (and other types of USB devices) aren't working, when in fact the driver got messed up because of bad leftover state in the Windows Registry. Almost impossible to know whether you're seeing actual trouble with Teensy, or if it's just unreliable Windows USB drivers.

Microsoft finally fixed these really unfortunate problems with Windows 10. But they never back-ported the fixes as updates for Windows 7 or Windows 8.

Please do your sanity a huge favor and use at least Windows 10 (or Linux or MacOS) so you're not running on an old Windows where USB would usually work but occasionally suffer from really confusing problems.

I have considered moving to Windows 10, but each time I have come across another way in which it is intrusive and Web-dependent, so I have put it off. I'll look at it again.

But: The trigger for this thread was USB- and Windows-independent. I have a Teensy 4.1 that went into a deep frozen state after more than a week of happily running by itself, not connected to Windows or to any other USB channel. By "deep frozen," I mean that power-cycling the Teensy didn't help. It was only after that that I started trying to get the Teensy reconnected to Windows via USB.

 

[Fenichel]

I started this thread to report that a Teensy 4.1, not connected via USB, had frozen after over a week of continuous operation. Rebooting had no effect, and it could not be restarted until the app was reloaded from the Teensyduino IDE.

The thread got sidetracked into a discussion of Windows versions, and I never heard a suggestion as to a possible cause of the freeze.

Now the same Teensy running the same app has frozen again, this time after 52 days of 24/7 operation. About 15 seconds after I de-power it and restore power, the tiny amber LED near its USB connection flashes once. Does anyone else have experience with this failure mode?

 

[kd5rxt-mark]

Are you using the millis() function for calculated delays ?? Are you handling overflow (as indicated, after approximately 50 days) correctly ??

Hope that helps . . .

Mark J Culross
KD5RXT

 

[Fenichel]

Thanks for the idea, but I never use millis().

 

[defragster]

Does anyone else have experience with this failure mode?

This seems oddly unique among the posts and history AFAIK ...
Really Odd

the Teensy was visible, and it was running its default Blink program

And this is really ODD as the two ways to get BLINK on a T_4.1 are #1:Manual Upload and #2: 15sec Restore only by holding the Program Button on a powered Teensy ~13-17 seconds and releasing it in that time frame. And neither of those are suggested as done?

And a failure after 7-10? days and 52 days is a big window where it ran for a respectable period.

Without seeing the code or any idea of what hardware is attached, and the process involved while running - except not actively attached or using USB ...

Have had some code run and programming or restarting was odd perhaps - but likely on a shorter run of bad code - and it may have been resolved with the 15 Sec Restore and then not recurred or needed further investigation.

 

[Fenichel]

And this is really ODD as the two ways to get BLINK on a T_4.1 are #1:Manual Upload and #2: 15sec Restore only by holding the Program Button on a powered Teensy ~13-17 seconds and releasing it in that time frame. And neither of those are suggested as done?

The first time (7+ days) I probably did try holding the Program Button, as you suggested, and the recovery can be attributed to that. I should have mentioned this. The second time (52 days), alas, I definitely did try the Program Button method, without success.

And a failure after 7-10? days and 52 days is a big window where it ran for a respectable period.

Without seeing the code or any idea of what hardware is attached, and the process involved while running - except not actively attached or using USB ...

Have had some code run and programming or restarting was odd perhaps - but likely on a shorter run of bad code - and it may have been resolved with the 15 Sec Restore and then not recurred or needed further investigation.