JLink hangs after reset from nrfjprog v10.10+

RE: JLink hangs after reset from nrfjprog v10.10+

Vidar Berg — Mon, 14 Nov 2022 09:40:50 GMT

nrfjprog will force the chip out of Debug Interface mode when you perform a reset, which is typically what you want after loading a new FW image. But this will also kill any active RTT sessions. If the chip had remained in debug mode it would have increased the overall power consumption of your device.

The workaround is to keep the debug session active by resetting the device from a Jlink commander session, or re-establish the debugger connection after a nrfjprog reset.

RE: JLink hangs after reset from nrfjprog v10.10+

lvh831 — Sun, 13 Nov 2022 07:23:22 GMT

I have the same problem. Either I have to run "r" or "con" in J-Link. I ran JLinkExe with -AutoConnect 1 but that didn't help. Is the problem is on JLinkExe or on nrjprog?

RE: JLink hangs after reset from nrfjprog v10.10+

Vidar Berg — Wed, 12 Oct 2022 14:37:43 GMT

Hello,

No, your issue description was clear, and I did report it internally too. It just seems like the nrfjprog team has not had a chance to follow up on it yet. I will send them a reminder.

RE: JLink hangs after reset from nrfjprog v10.10+

Rodrigo Brochado — Tue, 11 Oct 2022 20:48:07 GMT

Hello

Any updates on this?

I don't know if I passed the wrong information here. I meant that the commands "r" and "g" on the jlink commander worked, BUT I still have the problem described above.

I tested nrfjprog 10.16 today, because the latest nrfconnect 3.12.0 is compatible to its Jlink version, but the problem persist on nrfjprog 10.16.

Thank you.

RE: JLink hangs after reset from nrfjprog v10.10+

Rodrigo Brochado — Fri, 07 Jan 2022 15:24:29 GMT

Nice!
I can confirm that resetting in jlink commander works.

Thank you!

RE: JLink hangs after reset from nrfjprog v10.10+

Vidar Berg — Fri, 07 Jan 2022 12:38:17 GMT

I see the same now when testing here. That is, I stop getting RTT messages as soon as I peform the --debugreset. It does however work when I instead perform a softreset from Jlink commander (JLinkExe). Can you try the same?

Resetting in jlink commander:

> r /* reset and halt */

> g /* Start execution */

I will report this issue internally in the meantime.

RE: JLink hangs after reset from nrfjprog v10.10+

Rodrigo Brochado — Thu, 06 Jan 2022 13:05:51 GMT

Thanks for the answer, Vidar.

I've tested with --debugreset now and also with --hardreset (although this one should not work based on your info on power precautions) on v10.15.1 with JLink 7.50a, 7.58b and 7.60b, and it didn't worked either.

RE: JLink hangs after reset from nrfjprog v10.10+

Vidar Berg — Thu, 06 Jan 2022 10:00:10 GMT

Hi,

Have you tried to use --debugreset instead? nrfjprog is actually supposed to make the chip exit debug interface mode after a --reset to avoid excessive power consumption after programming (base current in debug mode is ̃around 3 mA). There was however a bug in nrfjprog 10.9 that prevented it from powering down the debug interface, so that would explain why RTT kept working after reset earlier.

Best regards,

Vidar