Could not find core in Coresight setup nRF52840 ?

Is the chip failed already ?

I can see LD2 (RED) is on, very dim.

The correct IO voltage depends on how you are you powering the dongle (see Power supply options) and the REGOUT0 setting if you use high voltage mode.

Hi Vidar,

Thanks for the reply,

I connected Vcc from J-Link to Vbus and GNd to GND,

It was working but now it's not,

Looks like the chip is faulty, do you reckon ?

Kind regards,

Rixtronix

Do you reckon my internal regulator is faulty ? I used external 5V to Vbus, it's still not responding...??

Regards,

Rixtronix

I can't pinpoint where the fault based on the information provided here.

What is the VTarget/Vtref pin connected to since it's 3.3 volts? It should be the same as the IO voltage, which you measured to be 2.2 volts

user91908 said:

Connecting ...
 - Connecting via USB to probe/ programmer device 0
 - Probe/ Programmer firmware: J-Link ARM V8 compiled Nov 28 2014 13:44:46
 - Device "NRF52840_XXAA" selected.
 - Target interface speed: 4000 kHz (Fixed)
 - VTarget = 3.313V

I can't pinpoint where the fault based on the information provided here.

What is the VTarget/Vtref pin connected to since it's 3.3 volts? It should be the same as the IO voltage, which you measured to be 2.2 volts

user91908 said:

Connecting ...
 - Connecting via USB to probe/ programmer device 0
 - Probe/ Programmer firmware: J-Link ARM V8 compiled Nov 28 2014 13:44:46
 - Device "NRF52840_XXAA" selected.
 - Target interface speed: 4000 kHz (Fixed)
 - VTarget = 3.313V