nrf5340 DK jlink not found

[allenboon]

Hello team,

I have used nrf5340 DK for some while. 

Today, I use DK board SWDIO & SWDCLK to flash my PCBA. But, suddendly my PC cannot found DK.

When DK connected to PC, device mananger was no response. Virtual seriort port and jlink both cannot enumerate. The LED5 also no lighting as below picture

,

I have measure DK power output, VDD and 5V both work normally.

This issue have occured on my two nrf5340 boards.

Can anyone help to solved this issue? Thanks.

Allen

[Menon]

Hello,

Can you once go through this ticket from my colleague? He has clearly explained whatever things you need to check, when DK is not detected by the PC. Please report back if everything stated looks good.

Kind Regards,

Abhijith

[allenboon]

Hello Abhijith,

Below is both DK response

1. The swithches are set to on, VDD, and default. The nrf5340 DK have another switches VEXT -> nRF and FLOW CONTROL which set to OFF and ON.
2. Micro USB was connected on short side.
3. Device manager did not show up anything when DK connected or disconnected.
4. The USB cable can use on another nrf52832 DK. So, I think USB cable is no problem.
5. DK cannot config on two different PCs
6. I have measured the power. Both VDD(3V) and 5V are working normally.

If any other thing need to check, please tell me.

Thanks

Allen

[allenboon]

Hello,

Add one more thing, DK's LED5 will turn on short times(maybe 2-5ms) then turn off when DK plugging in PC.

Allen

[Menon]

Hello,

Thank you for checking and clarifying the issue.

Today, I use DK board SWDIO & SWDCLK to flash my PCBA. But, suddendly my PC cannot found DK.

I assume you are programming a custom board  via SWD interface. Does your DK get unrecognized after flashing?  How are you powering the custom board? I guess you connected the VDD/GND/SWDIO/SWDCLK properly.

Kind Regards,

Abhijith

[allenboon]

Hello,

Yes, I connected VDD/GND/SWDIO/SWDCLK to our custom board. I think maybe Jlink hardware have broken, because the nrf5340 side function normally(I can see LED on). But, I do not know why Jlink hardware broken.