View Full Version : bricked teensy3?

11-10-2012, 01:09 PM

I seem to have bricked my teensy3 board. I'm trying to program it in a more-or-less bare-metal mode, without arduino, and similar to other small microcontroller platforms such as MSP430.

So I copied the toolchain, linker script, and setup files from the arduino distribution and set about blinking the LED. Lacking a schematic, I decided to try blinking every GPIO bit so that I could then drill down on where the board's LED was actually situated in GPIO space. Attached are the files I used to build the hex file (and also included is the fatal hex file itself); after building I used the interactive teensy tool to download and reboot. I'm on a linux 64-bit platform.

After rebooting (or inserting the micro-USB cable) the LED is either solid amber or dark (about equally likely) instead of the intended blinking. What's more, when I press the pushbutton, nothing happens on my Linux host USB-wise, and the teensy tool no longer sees the board to download a new hex file.

Anything I can do to recover the board? I realize main.c is a bit brutal, by configuring everything as a GPIO output and blinking them all indiscriminately, but I thought the pushbutton would always let me recover. Also, please consider releasing a schematic for the board.

The attachment is a .tar.gz file; this forum software would not allow it to be uploaded, so a pdf extension was added.



11-11-2012, 06:21 AM
I was able to recover. Holding down the pushbutton before plugging in the micro-USB cable did the trick. I guess this prevented any ARM code from executing; probably my code was disabling ezport or something like that.

11-13-2012, 07:43 AM
Nice find on the fix. That's a good one to remember in case that ever happens to me.