Device not turning on, however BLE works, LED5 flashes once

[avijay]

So I am using the NRF5340, and it has been fine for a few months now, however today, it stopped working and sending any data between the USB and laptop, the LED5 flashes once and not again. Using a multimeter, I found that there is power in the device, but it isnt recognized thorugh JLink or VS Code. However, I had flashed a BLE application onto the device before this issue, with an analog input, and when I tried it out, it worked. Please let me know what can be done!

[Priyanka]

Hi @Aditya Vijay   Glenyz 

This could be done only on previous DK versions where the Debug chip was a SEGGER chip. In the 5340DK and later versions of all other DKs, the Debug chip is the 5340SoC and it's not possible to re-flash the fw onto it. 

So if the issue is with your Debug chip (which could be the case), then please try using an external debugger, or you can use the DebugIN (P18) from another DK to flash onto this one.

-Priyanka

[avijay]

Hi Priyanka, I tried to use a J-Link Segger and unfortunately it could not read nor detect the nRF5340. I tried sending commands but it would not pick it up either. Are there any other steps beyond that?

[avijay]

Hi Glenz, thank you so much for your advice, I appreciate the support!

[Priyanka]

Please take a look at this Debug input and trace documentation for details on how to connect an external debugger to the SoC on the 5340DK. Please try this s that we can check if it's the debug chip's problem.

In case you have another DK (say, maybe another 5340DK), you can use the debug chip on that in order to program is SoC as well. Please refer here for the same.

-Priyanka

[avijay]

Hi Priyanka, could you kindly attach documentation for the first comment. I will try that and let you know. I unfortunately do not have another DK to test with, but am receiving two from Nordic support shortly.