Qualcomm Flight RB5 stuck in fastboot

[royb]

Hi devs, I've been working with the Qualcomm Flight RB5 drone (with VOXL SDK) for a few weeks, but it has suddenly given out. I suspect it may have been due to overheating, but am not entirely sure.

Since then it seems to always be stuck in fastboot. To rule out the influence of the peripheral boards, I've extracted the Qualcomm Flight RB5 mainboard and Thundercomm RB5 SOM from the drone, but with the same result. Finally, I followed the "Unbricking your VOXL 2" instructions in the docs, for which I used the "RB5 Flight QDL Image 9.1_QUP10" image. After successfully flashing the hardware and rebooting, the system still gets stuck in fastboot. In particular, lsusb lists the board as:

Bus 004 Device 118: ID 18d1:d00d Google Inc. Xiaomi Mi/Redmi 2 (fastboot)

And fastboot devices lists the board as:

ffbb5e0c	fastboot

Finally, after flashing it, I can visually see the board rebooting 7 times on startup. This seems to be in line with the slot-retry-count:b value when running fastboot getvar all:

(bootloader) parallel-download-flash:yes
(bootloader) hw-revision:20001
(bootloader) unlocked:yes
(bootloader) off-mode-charge:0
(bootloader) charger-screen-enabled:0
(bootloader) battery-soc-ok:yes
(bootloader) battery-voltage:3832
(bootloader) version-baseband:
(bootloader) version-bootloader:
(bootloader) erase-block-size: 0x1000
(bootloader) logical-block-size: 0x1000
(bootloader) variant:QRB UFS
(bootloader) partition-type:mdm1m9kefsc:raw
(bootloader) partition-size:mdm1m9kefsc: 0x1000
...
(bootloader) partition-type:ssd:raw
(bootloader) partition-size:ssd: 0x2000
(bootloader) has-slot:modem:yes
(bootloader) has-slot:system:no
(bootloader) current-slot:a
(bootloader) has-slot:boot:yes
(bootloader) slot-retry-count:b:7
(bootloader) slot-unbootable:b:no
(bootloader) slot-successful:b:no
(bootloader) slot-retry-count:a:0
(bootloader) slot-unbootable:a:yes
(bootloader) slot-successful:a:no
(bootloader) slot-count:2
(bootloader) secure:no
(bootloader) serialno:ffbb5e0c
(bootloader) product:
(bootloader) max-download-size:805306368
(bootloader) kernel:uefi

Does anyone have any other ideas on what to try?

[Vinny]

Hi @royb
We've never seen any of our devices show us as "Bus 004 Device 118: ID 18d1:d00d Google Inc. Xiaomi Mi/Redmi 2 (fastboot)"
That is either a serious corruption of the flash, or some wrong files are being loaded up during the unbricking.

Can you please double check your unbricking procedure and be sure to follow everything step-by-step?
https://docs.modalai.com/Qualcomm-Flight-RB5-QDL/

[royb]

Hi @Vinny, I just closely followed the instructions you referenced, but with the same result.
I'm using the exact same (latest) QDL image as in the instructions, which gets flashed successfully. After reboot, it still shows up as ID 18d1:d00d Google Inc. Xiaomi Mi/Redmi 2 (fastboot) however. I nevertheless went on to flash the RB5 SDK 1.1.2, which also seems to successfully finish, but after rebooting it still won't get out of fastboot.

Is there some way to check if the flashed QDL image on the device is corrupted? And are there any other options?

[Vinny]

HI @royb
Need to pull in someone from software here, I was just trying to ensure the basics were covered. Seems like you had that verified.

@tom

[royb]

Hi @Vinny and @tom, do you have any updates on this problem by any chance?

[tom]

@royb Just to confirm, you've already run through the unbricking process using the QDL program?

[royb]

Hi @tom,
Yes that's right. I followed the instructions linked by @Vinny and used the QDL image for the Qualcomm Flight RB5 with the name "RB5 Flight QDL Image 9.1_QUP10" from the developer.modalai.com repository. Is this indeed the right image? Or do I need the "VOXL2 QDL Image 14.1a_1.7.8" image by any chance?
Following those instructions, the result is as I described in my earlier comments.

[tom]

@royb You used the correct one.

I think you've followed the exact process I would've recommended. Unfortunately I don't have any further debugging steps to suggest and I would recommend filing an RMA for this drone: https://www.modalai.com/pages/rma

[royb]

Hi @tom,
Thanks for looking into this.
Do you think this is just something to do with the Thundercomm C5165 SOM or may it be affected by the Flight RB5 mainboard? So if I were to switch out the current SOM for a new one, should it be fixed?

[tom]

@royb If you have another SOM sitting around it wouldn't hurt to try