Teensy light only on for a few seconds

[AKmalamute]

I've recently built my 2nd phantom, and having nothing but problems.

Right now what's going on, is that when I first plug it into the computer, everything is fine ... then about a minute later, the keyboard becomes unresponsive. Also, the light on the Teensy is out. Unplugging / replugging bright the light on again for several seconds, during which time the keyboard is behaving normally. Then it goes out again. Unplugging / replugging sees the light flicker for a small fraction of a second.

If I leave the keyboard unplugged for several minutes, the invisible timer is reset; I get about a minute of keyboard before having to let it cool down again.

 Is this a fixable soldering problem, or did I somehow kill the microcontroller? I've only used it on one computer so far but it accepts $5 dell keyboards for multiple minutes without complaint so currently I'm assuming its not computer specific. Will research that next, however.

[Findecanor]

I think it could only be on the Teensy. You should replace it.
Do you plug/unplug to the Teensy directly or do you have a short cable to the outside of the keyboard?

[AKmalamute]

I think it could only be on the Teensy. You should replace it.
Do you plug/unplug to the Teensy directly or do you have a short cable to the outside of the keyboard?

I've created a cable with intention to facilitate a detachable cable. And yes, I blamed it first but I've since bypassed it with a cable that goes straight to the computer (also, a different computer) and the behavior is identical.

It's overheating. That's got to be why the time keeps shortening but will 'reset' a few minutes later. Not much room on that thing to generate heat so it surprises me, but I did have a heck of a time getting all the wires to solder in -- had to try three times plus the heat gun. Must have melted something critical.

Alright if any one else has input go ahead, but I'll see about replacing it too.

[arakula]

Sine the "light" on the Teensy 2.0 is programmatically controlled, it doesn't offer much of a clue. You don't state anything about the used firmware.

Since you describe your soldering as a bad experience, I'd suggest that you make extra sure that (assuming you used the lines on the small end) you didn't create a blob on the GND line that's large enough to spill over to RST when it gets warmer.

[AKmalamute]

Sine the "light" on the Teensy 2.0 is programmatically controlled, it doesn't offer much of a clue. You don't state anything about the used firmware.

Since you describe your soldering as a bad experience, I'd suggest that you make extra sure that (assuming you used the lines on the small end) you didn't create a blob on the GND line that's large enough to spill over to RST when it gets warmer.

There's no reason to believe firmware would let the light stay on but tell it to go off at a random time later. Also, the light going off coincides with unresponsiveness, and acts successfully of an indicator of when the keyboard has stopped working.

This firmware was built from Metaliqaz' piece of software.

And you obviously don't have a phantom, or you might know that the GND that's next to RST are both blank. No blobs at all that are near either because those pins aren't used.

[dorkvader]

And you obviously don't have a phantom, or you might know that the GND that's next to RST are both blank. No blobs at all that are near either because those pins aren't used.

Hey chill out, he just wants to help.

I think it's one of the following:
broken or damaged teensy
soldering issue (I have had some that will fail after some time due to intermittent joint)
Shorting / grounding issue (My first KMAC and skeldon (phantom) had this issue where the case was shorting out some leads and ti would shut off randomly)

Post pictures, if we see anything we'll tell you areas to look at or reflow or whatever. Worst case scenario is that your have to replace the teensy or mail it to someone to get it repaired for you.

[AKmalamute]

Hey chill out, he just wants to help.
[...]
Post pictures, if we see anything we'll tell you areas to look at or reflow or whatever. Worst case scenario is that your have to replace the teensy or mail it to someone to get it repaired for you.

Sorry didn't mean to sound mad. It was a good suggestion until I looked at my board and realized that was nigh impossible.

It's a little late for pictures as I've traded with coworkers for their teensies (bought during the last GB but never used). So far, so good. This is definitely the longest run-time for this keyboard but we're still barely past 10 minutes. Still, I think the old controller was damaged somehow.

This whole reply was typed on my phantom. Lights are still on, all as expected. I'm guessing the heat-gun melted something important so - word to the wise, don't overheat your 32u4. 

[arakula]

There's no reason to believe firmware would let the light stay on but tell it to go off at a random time later. Also, the light going off coincides with unresponsiveness, and acts successfully of an indicator of when the keyboard has stopped working.

You're absolutely right - but it can be an indicator that the Teensy rebooted into the Halfkay boot loader, or simply went belly-up completely. Assuming Windows, which devices are reported by the Device Manager after the light goes out?

And you obviously don't have a phantom

Correct. I'm strictly a Model M guy  ... but re-checking all solder points is always a good first step, and, if used, these two points are dangerously close and could be responsible.

Anyway, since you've already replaced the Teensy, it's all a bit academical now ...

[AKmalamute]

I've brought the 'dead' disconnected teensy to work, which is set to play a sound when a USB device is unplugged. Here's what I've seen:

When first plugged in, the light is on, and the device manager shows an extra keyboard. I can't see where it says one of them is an epsilon but we'll overlook that detail for now.

After about a minute, the 'unlugged' event sound is played, and the keyboard disappears and I don't see another device show up in the device manager. I also have the teensy.exe program, which I've left running, and it did not see a teensy (in programming mode) either. So it was in limbo for a variety of seconds.

Then the unplug event sounds again, at random moments (I couldn't detect a pattern or rate or rhythm) for a total about about six unplugs across the next minute. During none of those did the LED light come back on. However, for one of the segments in the middle, and at the final moment at the end of it, the 'reboot' light of the teensy.exe program was un-grayed (teensy was in programming mode).

After watching it be stable for another minute or two, I told the executable to reboot the teensy, which it did and it caused the extra keyboard to show up again for the full minute. After that the unplug, unplug-again cycle repeated, with at least one of the segments in the middle showing as programmable in the executable, and again out of programming mode but not a keyboard, and it seems to have stabilized in programming mode.

[arakula]

I fear that there isn't much that can be done, unless you got someone with a reflow oven nearby. If your hot air gun just partially ruined one of the SMD solder joints, a (controlled!) reflow operation might cure it, although I'm not very optimistic.

[AKmalamute]

If your hot air gun just partially ruined one of the SMD solder joints, a (controlled!) reflow operation might cure it, although I'm not very optimistic.

None of the SMD parts have _moved_, though. I messed up my ergodox's controller bad enough two of the SMD parts came off and I had to reattach them with the giant screwdriver bit, operated in a panic (I guess those are called spade bits?). Despite having pieces on semi-sideways it's been fine for the six months I've been using it (minus the two months the cable connecting the halves was cut but that's hardly a uC problem)

My current assumption is still that I damaged the 32U4 by overheating it. But as you point out, it's academic since I've moved on with my life by swapping for a less recalcitrant microcontroller. Still, someone out there some day is going to experience similar breakage and find this long-dead thread. I wish you luck, future hacker...