HalfKay does not run upon pushbutton press; verified not USB cable issue

[owl]

Hello! I have with me a brand new Teensy 2.0 and I have been trying to use the Teensy Loader to program it. But it seems like HalfKay just does not run when I press the push button.

I have Teensy Loader 1.48 and the machine I am connecting to is running Ubuntu 18.04.4.

When I connect the Teensy to my computer, the LED starts blinking.
When I press the push button, the LED stops blinking.
But Teensy Loader doesn't do anything and still says to press the button to enter program mode.
I have the udev rules copied to the preferred location /etc/udev/rules.d/49-teensy.rules and I know these rules worked because I can still program my other Teensy.
I know it is not the USB cable not having data lines, because I have been using that same USB cable with my other Teensy.

I have tried rebooting my Linux computer and trying again--no luck.
I have tried holding down the push button while plugging in the Teensy--no luck.
I have tried connecting the Teensy to my macOS machine instead and running the Teensy loader--no luck, same problem.

On Linux I have tried these instructions https://www.pjrc.com/teensy/check_halfkay_linux.html and have verified that, when the new Teensy is plugged in and I have pressed the push button, nothing new shows up in the lsusb output (and also nothing new shows up if I $ ls /dev). I tried this with my old Teensy and I see Teensy Halfkay Bootloader in the lsusb output.

On macOS I have tried these instructions https://www.pjrc.com/teensy/check_halfkay_mac.html and have verified that "Composite device" does not show up on the profiler when the new Teensy is plugged in and I have pressed the push button. I tried this with old Teensy and "Composite device" shows up as expected.

It is as though the push button just turns the Teensy off.

I didn't buy this Teensy 2.0 directly from Adafruit but it was resold to me in the original unopened Adafruit packaging, from the same seller that sold me the old working Teensy. The LED blinks orange.

I have utterly no idea! Any help would be enormously appreciated! Happy to provide more info, I just don't know what else to add.

 

[PaulStoffregen]

Can you show us a photo?

It should be genuine if if came from Adafruit, but everything else you've described sounds like a counterfeit.

 

[owl]

Of course! I hope these pictures are clear enough?

 

[owl]

Also, maybe my soldering is the problem?! But so far I have been troubleshooting it with my USB soldering work taken out of the equation, like so:



And also with it in the equation, the LED light blinks when the Teensy is plugged in, and turns off when push button is pressed, so I really don't think that's the issue T^T:

 

[PaulStoffregen]

That looks like a genuine board.

Maybe try watching the Linux syslog messages as you press the button. On my Ubuntu system "tail -f /var/log/syslog" does it. You should see the kernel tell you info about the USB disconnect and connect events, and what specific device it sees and what drivers it loads. Maybe that will reveal info about what's wrong?

 

[owl]

Oof... absolutely nothing happens, both when I plug/unplug the Teensy (even though the LED blinks), and when I push the button and the LED stops blinking. The syslog just doesn't output anything at all. I sanity checked against my other Teensy and it logged a bunch of stuff on plug and unplug.

 

[larry_berlin]

It looks like something is wrong with the USB hardware on your teensy 2.0.
Maybe USB connector, PCB, 22 Ohm resistors or even 32U4.

 

[PaulStoffregen]

Are you testing by plugging the USB cable directly into Teensy? Or is it going through those 2 connectors and wires in the 2nd photo on msg #4?

 

[owl]

No, I am plugging the cable directly into Teensy, as in the first picture (though I have tried it both ways, and both give me the same results). Thank you for your continued help! Thanks Larry also !

 

[PaulStoffregen]

If the LED was blinking, and stops blinking when you press the button, that's a pretty sure sign the chip is working. With no USB activity on a known good cable, the only likely cause is damage to the USB part of the Teensy 2.0. There's not much to break, just the 2 data connections, and the 3V regulation (the USB section of the chip runs not on 5V but on 3V created by its own built-in regulator) which should appear on that 1uF capacitor near the USB connector.

 

[owl]

Is it possible I got a broken board? Mechanically I have been really gentle with the USB (and it looks fine inside), so I really don't think I did any mechanical damage. Do you think I could have shorted something somehow? For example if one of the data lines touched power or ground or something while Teensy was plugged in, would this permanently damage the data lines? I'm guessing I now have to get another Teensy and resolder everything, so any other tips on what to not do would be helpful!

 

[PaulStoffregen]

If you have a voltmeter, connect its negative lead to GND and try measuring both sides of every larger capacitor. All of them should be 0V (connected to GND) on one side and either 5V or 3V on the other side. Maybe something got shorted out and you'll find one that doesn't have voltage?

 

[owl]

I do have a voltmeter! What I don't have is any idea what I'm doing

But I tried my best--here are my results. I don't even really know which ones are capacitors (hence my having measured everything), but the big brown ones seem to be OK? The tiny brown one by F6 seems to be zero on both sides... but you specifically said to measure the larger ones.