Thingy:91 not detected in nRF9160 mode

[Gwen83]

Hello everyone,

I’m facing an issue with my Thingy:91. It was working fine throughout the day, but after flashing a program onto the nRF9160, my computer no longer detects the device when it’s connected in programming mode or in normal mode with the nRF9160 active.

Here’s what I’ve tried:

1. When I turn on the Thingy:91 in nRF9160 mode, it is not recognized by my computer.
2. However, it is properly detected when in DFU nRF52 mode.
3. I’ve tried flashing a .hex file to the nRF9160, but since the device isn't detected in this mode, I can’t proceed with the operation.
4. I also tried reflashing the nRF52840 firmware in DFU mode, hoping it would resolve the communication issue, but this didn't help.

Has anyone experienced this issue before, or do you have any suggestions to restore the nRF9160 detection on the computer?

Thanks in advance for your help!

[Achim Kraus]

The Thingy:91 has two components:

- the communication bridge for USB / Bluetooth LE, the nRF52840

- the modem and app mcu, the nRF9160

I guess, you flashed the nRF9160 app to the nRF52840. With that, step 4 should be the fix.

Do you use just USB and McuBoot? And you used the small SW4 to enable the boot mode? That's the boot mode of the nRF52840.

If so, which of the of the images did you apply to the "DFU nRF52"?

img_fota_dfu_hex  and thingy91_nrf52_connectivity_bridge_2024-03-13_af2b60d2.hex (or newer, but in the img_fota_dfu_hex)?

Once you applied that, then the Thingy:91 should be able to connect via USB again.

Then don't use SW4 (small) to enter the boot mode, use SW3 (large) to do so. with that, the nRF9160 will enter the boot mode and you will be able to apply your app to that.