Issue: nRF52840 is NOT working without USB on Thingy91_PCA20035

[Dheeraj]

Hi,

I am working on the asset_tracker application. 

I have integrated the "lte_ble_gateway" into the asset_tracker application and able to get the BLE values from nRF52840_PCA20035 to nRF9160_pca20035, sending same values to the nRF cloud.

But this is happening only when the thingy91 got connected with USB.

If I remove the USB cable and keep Thingy91 as a standalone device and reset (power cycle) didn't receive BLE values from nRF52840_PCA20035. 

And seen the "err: Scanning failed to start, err -12".  and NO BLE values observed from nRF52840.

Please help me with the possible solution to fix the above issue. 

[Sigurd]

Hi,

1) I assume you tested this file ?

hci_uart_with_usb_uart_bridge_nrf52840_pca20035.hex

Dheeraj said:

The nRF52840 should send BLE values, though we removed the USB and power cycle the Thingy91 using SW3/SW4.

2) How did use implement the power cycling using SW3/SW4?

[Dheeraj]

Hi Sigurd,

Thank you for the response. 

Sigurd said:

1) I assume you tested this file ?

hci_uart_with_usb_uart_bridge_nrf52840_pca20035.hex

Yes, you are correct. 

From the ticket https://devzone.nordicsemi.com/f/nordic-q-a/52689/nrf9160-lte-sensor-gateway-on-thingy-91/226450#226450 

we are testing "lte_gateway_thingy91_v1.1.0_R2.zip ==> hci_uart_with_usb_uart_bridge_nrf52840_pca20035.hex and lte_ble_gateway_nrf9160_pca20035ns.hex". 

Flashed "hci_uart_with_usb_uart_bridge_nrf52840_pca20035.hex" on nRF52840 and 

Flashed "lte_ble_gateway_nrf9160_pca20035ns.hex" on nRF9160. 

Observed test results with the above Images:

With USB connection:

Observed BLE, LTE, and Cloud initialization.
Observed thingy91 connected to nRF cloud
Flipped thingy91, but no messages on the nRF cloud.

Without USB:

No LEDs are blinking Lost connection with cloud

To recover the device, Given Power cycle by changing ON/OFF switch on Thingy91 :
Observed RED and Blue LED colors continuously, and NO nRF cloud connection though we wait for 10 Mins.

Looks like the Image is crashing. 

Connected back to USB to observe the console logs and observe the Errors (UART issues)
The screenshot has been captured and attached. 

Another issue, we often observed is,  

After we porting the changes (nrf.diff and zephyr.diff for v1.1.0 branch) given on the other thread, we are able to see the following errors:

[00:00:00.946,105] <err> bt_driver: Unknown H:4 type 0x92

[00:00:00.946,105] <err> bt_driver: Unknown H:4 type 0x00

<wrn> bt_driver: Discarding event 0x3e

We have observed these issues when we tried to test thingy91 for a long time like 5Hrs. Once this warning started popping, other tasks are not working (For example GPS, Flip). 

After some time, the device getting disconnect with the nRF cloud.  The device never comeback to recovery by itself. 

Need a manual power cycle to get the device back to the normal state. 

From the above, we can see/understand that the HCI_UART interface is not working as expected and the behavior of BLE is unknown in Thingy91 (PCA20035).

Request from our end: We are happy to work along with you to fix this issue at the earliest, by raising this issue as a private. Because of this issue, we are missing our final deadline for production. 

I hope you understand our urgency. Please let us know. 

Sigurd said:

2) How did use implement the power cycling using SW3/SW4?

I am sorry for the confusion, I was using the ON/OFF button on thingy91 to give power cycle. I didn't Implement any new handlers for SW3/SW4. You can ignore this. 

Please help us as we are blocked with this issue. 

[Sigurd]

Hi,

Dheeraj said:

We have observed these issues when we tried to test thingy91 for a long time like 5Hrs

Dheeraj said:

After some time, the device getting disconnect with the nRF cloud

 Are you using the latest modem firmware ?If not, please update the modem firmware on the Thingy:91 to modem version 1.1.0 (can be download from this link, see this guide on how to update the modem fw).