TeensyLC won't load a sketch

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raflyer

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Hi,
I just bought 3 TeensyLC and soldered pins on them for use in a breadboard. First 2 Teensy's worked great, 3rd one is stuck at the point where it says, Please press the PROGRAM MODE BUTTON on your Teensy to upload your sketch.

I do and nothing happens. I am using Arduino 1.6.1 and Teensy Loader 1.22 I tried uploading the Basic Blink sketch.

I notice that it seems to be getting warm while plugged in to the USB port towards the micro usb plug on the TeensyLC. I have triple checked with a 10x viewer for any shorted tracks. All look great. Win7 see's it as a Teensy no issues, all voltages are normal. 3.30 and 5.04

Is there a way to do like a hard reset or something?

Thanks
Rob
 
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Seems you didn't function test them before soldering? You can readily upload and test them before soldering and I saw that as a recommendation I followed.

Paul or someone may pop in here - but side by side scanning two of them pin for pin to the component side may show something shifted from the heat. Feeling warmth isn't normal - so look hopefully the side by side scan will show what may have happened.

I've powered up 2 LC's and now four 3.1's and had only success the past weeks. You might unplug the LC - press & continue to hold the button while plugging it in and then hit upload as you release the button in some fashion while it is the only Teensy connected.

They are factory tested and pretty immune from bad onboard software because of the design where a second onboard processor gets first crack to keep the primary unit offline while it gets it ready to program.
 
It worked as it was doing the blink led that it comes preloaded with. I even uploaded one sketch, the button test to verify it. It was on the second sketch upload that i ran into issues. I will try holding the button.
 
Good luck - are you on Windows? Are you getting 'device not recognized' pop-ups? I did yesterday when I put on an example sketch with a 'while (!Serial)' type loop - and I did the button press to keep it quiet so it could be programmed and went to a setup loop more like: "while (!Serial && (millis() <= 6000));" that seems to allow it to act normally. The other thing I do is turn on the LED ASAP so I know when it is starting the sketch - this one pounds the LED off/on while stuck waiting for the Serial.

Code: 
#define qBlink() (digitalWriteFast(LED_BUILTIN, !digitalReadFast(LED_BUILTIN) ))
void setup() {
  Serial.begin(38400);
  pinMode(LED_BUILTIN, OUTPUT);
  digitalWrite(LED_BUILTIN, HIGH);   // On Teensy must set to OUTPUT before setting value
  while (!Serial && (millis () <= 4000))
    qBlink();
}
 
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If you have a voltmeter, check the VIN or VUSB voltage. Whenever a board isn't responding, check first if it's getting proper power.
 
Check your USB cable - try another one.

I just fought for an hour with a working LC. It was getting power and running the Win7 uploaded sketch. But would not show in PORT or program. Tried a new cable and all is well on this Win 8 tablet. I'm 'sure' that cable was working before - but now retired.
 
Tried another cable and still doesnt load the sketch. Win 7 sees the Teensy correctly and i have the correct voltages. Its stuck in the reload mode or something.
 
I'll hope Paul can get you to a running state. You said you have uploaded to two other LC's and I suppose they still work, and you uploaded to this one before - so it used to work. All I had was suspecting the sketch you left on it is somehow throttling the hardware/USB - or some interference from applying molten metal. Does your prior sketch blink the LED to show a sign of life?

Did you only pin the two long sides and not the end and internal pins? I socketed my internal pins and almost powered it up on the breadboard with the 'placeholder' pins in the breadboard - which would have tied VUSB to GND.
 
I only solder the edge connections. There is something going on, don't know how to explain it but I have 4 Teensy 3.1's and 4 TeensyLC's The Teensy LC is very touchy when up loading a sketch. By this I mean, on my 3.1's I am driving some stuff with PWM, I can make multiple sketch uploads to make changes with no issues. The LC version, I have to disconnect ANY load before they will program. This last one I forgot to unhook the load from the PWM while updating the test sketch and now it's locked up.
 
Ok, i'm on to something here. Just had another lockup on file upload. On Win7 op system, when I plug in the Teensy it wants to load drivers for it. Well unbeknown to me, behind my arduino IDE window was a small pop up that said you must reboot pc for changes to take affect. I didnt see it when i tried to upload to the teensy it lokced it up. SHows up as a Teensy rawHID instead of the Teensy Flight COntrols like the rest of mine. So i deleted all my usb stuff in the device manager, let it reload it all, thenplugged the Teensy and let it install then reboot pc and presto, Teensy now accepts uploads. Catch.... It only worked on the one, still have the other LC stuck in upload. Maybe this info will help Paul??
 
Awesome you made progress. Did you repeat the long press over connect step? As in this case the USB system is getting paralyzed - and this is one way to try to direct it's energies.

Only thing worse than modal dialog stuck in your face when you don't care - is the dialog you need to see that hides under stuff.

I typically have my sound off - not sure about you - but when you here those add remove tones they are often informative as to hardware state or health of the cable.
 
That's not weird - it's Windows - one got orphaned/ghosted. Very confusing. Goes away on reboot, or from DevMan. If you load the TYQT it will indicate the name and Serial# of the active Teensy's and let you see the active com port. (you may need to power cycle them to have USB wakeup let TyQt peek at them). And you can use it to do a serial monitor on all of them at once as one or more windows. Planned TyQt update will allow a friendly name per device maybe - for now you need a posted note stapled onto each one.
 
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