Unable to use External J-link debugger with nRF52840-DK

RE: Unable to use External J-link debugger with nRF52840-DK

Simonr — Wed, 18 Dec 2019 06:44:23 GMT

Glad you were able to figure it out!

Best regards,

Simon

RE: Unable to use External J-link debugger with nRF52840-DK

Jagbir — Tue, 17 Dec 2019 14:22:05 GMT

It was the custom cable which was the source of the problem. This morning I received a 20 pin to 10 pin JTAG adaptor with a cable with which I was able to program the DK through J2 USB (SES asks me which J-link to connect) or J3 USB independently or both USB plugged together. I have always used SW9 in VDD position because when SW9 is in USB position there is insufficient current to drive the LEDs. The SW6 position is irrelevant for programing purposes but we need to toggle to default position to see the LEDs or rest of the circuit power.

RE: Unable to use External J-link debugger with nRF52840-DK

pdpro — Mon, 16 Dec 2019 23:47:13 GMT

May you attached a high resolution image of your whole setup as Simonr suggested?

RE: Unable to use External J-link debugger with nRF52840-DK

Jagbir — Mon, 16 Dec 2019 13:45:26 GMT

By space I mean the room on the new PCB which I am spinning with nRF52840. I have just purchased the J-link plus last week and the nRF programmer can display the J-link connected with J-link serial number.Hence, I am assuming that J-link plus is not the problem.

RE: Unable to use External J-link debugger with nRF52840-DK

Simonr — Mon, 16 Dec 2019 11:16:35 GMT

What do you mean by "I don't have enough space on my board"? Isn't this an nRF52840-DK which already has an on-board debugger? You say that you were able to use another DK as an external debugger, but not the other J-Link. Are you able to confirm that the J-Link Plus is working, as it seems that the setup is correct?

Can you also upload a high-resolution picture so I can confirm that it is correct?

Best regards,

Simon

RE: Unable to use External J-link debugger with nRF52840-DK

Jagbir — Fri, 13 Dec 2019 21:03:49 GMT

Thanks for the inputs using which I I was able to program this nRF52840-DK using another nRF52840-DK . However, I am still unable to program this DK using a Segger J-link plus. I have checked my cable connection again, they seem to be fine. I have also tried an external pull up on SDIO line but still it does not work.

RE: Unable to use External J-link debugger with nRF52840-DK

Jagbir — Fri, 13 Dec 2019 21:02:37 GMT

I don't have enough space on my board that's why I do not want to use an OB debugger.

I was able to program this nRF52840-DK using another nRF52840-DK . However, I am still unable to program this DK using a Segger J-link plus. I have checked my cable connection again, they seem to be fine. I have also tried an external pull up on SDIO line but still it does not work.

RE: Unable to use External J-link debugger with nRF52840-DK

Simonr — Fri, 13 Dec 2019 12:53:35 GMT

Why do you want to use a J-Link probe on the nRF52840 DK in the first place? Please try what pdpro suggested and power the chip using J3 and set the chip into nRF ONLY mode. You can also try programming the chip using nrfjprog or nRFConnect for Desktop to see if the issue persists on multiple platforms.

Best regards,

Simon

RE: Unable to use External J-link debugger with nRF52840-DK

pdpro — Fri, 13 Dec 2019 01:09:01 GMT

Where is your USB cable connected? (I hope it is connected to J3). Also, slide the switch SW6 to nRF ONLY side.