Bricked RedBear Duo on first app flashing

I received my two new RedBear Duo boards today. I provisioned both for my network then added them as devices on the device page. All well up to that point.

I noted down the firmware levels the two boards came with as Version 0.2.3. With Bootloader at version 3.

These are old levels as my working board is at 0.3.1 and Bootloader at version 5. The iOS provisioning app seems to have a function to install new firmware which it prompted me to do. But when I selected it the app crashed every time. I installed the Android version of the app but it never gave an option to upgrade the firmware.

Since everything seemed OK with the Particle site (device registered) I decided to flash my app into one of the new boards. The flashing went through a lot more cycles of the flashing magenta then I normally see. At the end the board is bricked. If I go to DFU-mode the serial port is not active so there is no way to recover through the USB serial port.

I have a few questions:

  1. Was this caused by the firmware being at 0.2.3?

  2. Does the flashing process include trying to install new firmware on the RedBear Duo and was that the reason for the extra magenta flashing.

  3. I assume the only recovery is to flash a new Bootloader which requires the RBLink board. Is that correct?

The second new board I will update to the latest firmware before I try flashing any code into it. Will probably use the Arduino IDE instead of Particle website for first flashing of my code just to be safe.

In DFU Mode you only have a DFU interface available and not Serial by design.

What OS are you using on your computer?
With Windows you need DFU drivers and dfu-util to talk to the device.

Consequently this isn’t required either

I am using Windows. The DFU util/drivers are installed and I have used it several times the last two months to load the latest firmware to my first board.

But while testing today I had the Window’s Device manager screen open and had assumed since I did not see a COM port available when I was in DFU mode that the DFU util would not work so I did not even try. What you seem to be saying is that the special drivers allow direct access to the USB port and it is normal not to see a COM port listed on the Device Manager screen.

I will give the DFT-util a try tomorrow. Thanks

USB is a multi purpose interface and Serial (USB CDC) is only one of them. You wouldn’t expect to see a COM port when you attach a USB HDD or a USB camera either.

Just did a “DFU-util -l” and the board responded!

Thanks for setting me straight on that. I just made the bad assumption that no COM port meant there was no way to communicate with the board and did not even try.

I guess once I make every mistake possible I will be an expert.

ScruffR, thanks for setting me straight.

I did wonder how I could have killed the BootLoader by doing an app flashing.

I have flashed the firmware parts 1&2 several times to the other board but have never flashed the BootLoader code. Is that something I need to do since it is at level 3 and the latest is 5?


Hey Turbo3 did you ever get your duo working correctly, I am in a similar situation, just got my duo, came with a 2.4 version (surprisingly enough after one year) so I tried to do the upload using DFU-util but ended up messing up now the duo wont come up to full functionality, it just flashes the blue led and the Cyan, however when I put it in the DFU mode it responds to dfu-util -l
, not sure where to take it from here.

Any help would be very much appreciated it.

Been on vacation and I did not have my password available to log in and respond.

Yes, I got everything working again. I will need to look at my records to see what I did.