Several seemingly DOA Teensy Micromods.

Development Boards MicroMod
1

Hi,

I have a system that I’ve been developing for a remote application. Before traveling for on-site testing, I thought I would make sure that my spare Teensy MicroMods were ok.

I tested three fresh-out-of-the-sealed-ESD-bag Teensy micromods and they would not enumerate on USB. I tested with three carrier boards, two cables, and two laptops. Nothing worked for these three new Teensy Micromods. No blinking LED, no enumeration.

My development Teensy MM works fine in all these configurations. Supply voltages (5 and 3.3) are good on the ATP carrier board.

Am I being dense and forgetting something obvious? I’ve been using the Teensy ecosystem for many years with probably 5 different board versions. I’m annoyed to have left it so late to test the boards.

Any ideas? Is there a recovery procedure for the Teensy MM that might be worth trying?

Doug

2

Any comments from SF? This is a bit urgent for me.

Regards

Doug

3

Double-check that the pins don’t have some extra flux or something https://learn.sparkfun.com/tutorials/mi … e-overview on both the Teensys and the carrier boards Also check for corrosion, bent pins, etc

Just to be clear: the old Teensy will work in the old or new carrier board, and the new Teensys will not work in the new or old/known-good carrier board?

4

I’ve looked at them under the microscope and nothing is obviously problematic with the bad devices.

The bad and good devices are, I think, roughly the same age. The good Teensy MM will work in all carrier boards, and the “bad” Teensy MM will not work in any of them…

I have now tested with 4 carrier boards. Two from Sparkfun and two that I built. The good Teensy works in everything, and the problem Teensys neither run the “blink” program they are delivered with, nor enumerate on the PC. They were brand new out the ESD bag, so they should have the “blink” program run when power is applied.

Doug

5

Were they purchased from us? If so head over to www.sparkfun.com/returns (contact vendor if purchased elsewhere) and we’ll get ya squared away

6

Yes, they were purchased from Sparkfun. Unfortunately, I am now out of the country so it will be some time until I get back to this.