D21G - 'bricked', hardware reset possible?


when developping application software on the D21G, a flashing resulted in 'failed'.

Now the USB COM port is no longer detected on the PC (no hotplug event detected).
Swapping PC and cable does not solve anything.

It seems the bootloader is still there (as the display backlight is 'pulsing').
Is there any possibility to perform a factory reset?



Thomas De Gussem
Thomas De Gussem
| 3 1 2
Asked on 8/17/17, 10:06 AM

Hello! I know this is an old post, but I had the same problem and unfortunately I had no success with your method. I did some more research (I admit it was not particularly easy to find) and found this forum post: https://industruino.com/forum/help-1/question/early-d21g-adopter-need-some-documentation-326

Quote from the post:


1) The bootloader runs for 5 seconds after the board is powered on, reset or a sketch is uploaded (you can tell when the bootloader is running by the "breathing" of the LCD backlight).

2) The bootloader can be forced to run indefinitely until a new sketch is uploaded (or the board is powered off) by pressing the reset button twice (double tap)."

Basically, this is what you do:

  1. Take the cover off and locate S1 ( the reset button) underneath the LCD.
  2. Connect your USB and power up the Industruino.
  3. Within 5 seconds, press S1 twice (double tap). The LCD  should now "breathe" indefinitely.
  4. Now you should find the board in the Tools -> Port menu. Select it.
  5. Upload an empty sketch to the Industruino.

Hope this helps others with the same problem!

Markus Myklebust Myrstad
Markus Myklebust Myrstad
| 3 1 2
Answered on 2/16/18, 9:29 AM

Thanks for your feedback Markus, that is indeed the way to handle that on the current D21G topboards. We also have a note on the reset procedure here https://github.com/Industruino/libraries

on 2/17/18, 5:02 AM

Hola a todos Llegue a este foro porque estoy teniendo el mismo problema, en un inicio pude cargar un programa de manera normal en el Industruino 32u4, luego empece a trabajar con el Arduino Uno y ahora que quiero volver a trabajar en el Industruino 32u4 no puedo ya que no es reconocido en el puerto COM. Estoy intentando hacer lo que se indica en esta pagina pero no hay resultado, el lcd empieza a flashear y me sale el msj de que no fue posible la carga. Tambien he instalado el watchdog pero no sucede nada :( Si alguien tiene algun otro dato se lo agradeceria mucho.

on 1/24/21, 7:03 PM

OKay, I'll answer this myself, as this could be helpfull for users experiencing the same issue:

The 'bricked' state is a classic flashing error: flashing is unsuccesfull and corrupts application program. bootloader starts, but once 'broken' application is starting, USB COM port is no longer detected.

To recover:

1. make a small (empty) sketch
2. press the reset S1 >> press 'upload' in Arduino IDE > wait until 'uploading apears >> release S1

this timing is very critical. I had to try > 50 times  |:(  . the best result is to press 2 times on S1, somwhat 0.5seconds apart . then Windows detetcs the COM port for a split second.



Thomas De Gussem
Thomas De Gussem
| 3 1 2
Answered on 8/17/17, 11:19 AM

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Asked: 8/17/17, 10:06 AM
Seen: 4128 times
Last updated: 2/16/18, 9:29 AM