Reset when switching on modem

RE: Reset when switching on modem

Artnia — Mon, 02 Feb 2026 12:48:37 GMT

Hi Hakon,

thanks a lot. That was it 🙂

RE: Reset when switching on modem

Hakon — Mon, 02 Feb 2026 11:48:41 GMT

DEC0 should not be supplied by 3.3V. This is likely the reason for why you are seeing the strange behavior. Please cut the 3.3V line that goes to the DEC0 pin but leave the capacitor still connected. See if this fixes the issue for you.

RE: Reset when switching on modem

Artnia — Sat, 31 Jan 2026 15:33:54 GMT

Hi,

in my own software reset reason is

[00:00:00.302,276] <inf> Reset reason: 0x00000000

 // Get reset reason. 1=RESETPIN, 2=DOG, 196611=CTRLAP ...
 // docs.nordicsemi.com/.../power.html
 uint32_t reset_reason = nrf_power_resetreas_get(NRF_POWER);
 nrf_power_resetreas_clear(NRF_POWER, reset_reason);
 LOG_INF("Reset reason: 0x%08X", reset_reason);

I get reset also with at_monitor sample which switches modem on via code, instead of AT commands.

Also without any custom overlay but just by using the 9151dk as target board I get the same behavior.

Did you have a chance to check the schematic?

RE: Reset when switching on modem

Hakon — Thu, 29 Jan 2026 09:51:22 GMT

[quote user="Artnia"]is there a command for reading RESETREAS via AT?[/quote]

I don't think so, but you read it from software.

RE: Reset when switching on modem

Artnia — Wed, 28 Jan 2026 15:47:16 GMT

Hi Hakon,

is there a command for reading RESETREAS via AT?

Attached is the schematic, would be nice if you made the ticket private.

Thanks!

devzone.nordicsemi.com/.../PublicSchematic.pdf

RE: Reset when switching on modem

Hakon — Wed, 28 Jan 2026 15:12:50 GMT

Also, can you read out RESETREAS register to check what it says?

RE: Reset when switching on modem

Hakon — Wed, 28 Jan 2026 15:10:19 GMT

Hello,

should I make the ticket private? Can you share the design?