Is there a way to truly hard reset the nRF9160 without power cycling?

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

Sashi — Wed, 22 May 2024 16:45:26 GMT

I also still see the issue, I don't think this is a new one, and if there is anything to resolve the issue, it would be ideal to post it here. I worked around this in hardware by adding some circuits that are able to to a true power cycle, but a software only solution is still needed.

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

Didrik Rokhaug — Wed, 22 May 2024 15:54:23 GMT

Hi AnnaQ,

I recommend that you open a new ticket, as there has been a lot of changes and improvements in the last two years, so while the symptoms might be similar, it can still be a different problem.

One thing you can check before you open a new ticket is if you have triggered the modem's reset loop restriction.

Best regards,

Didrik

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

AnnaQ — Mon, 20 May 2024 09:23:08 GMT

Hello, we are experiencing the same problem. We have tested with both mfw 1.3.5 and 1.3.6. We have several units out on the field that need a power cycle to reconnect to the network. Have any of you others Stratosphere , Sashi or GJSea found a solution? Do you have any input Didrik Rokhaug ?

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

Stratosphere — Thu, 16 Nov 2023 14:19:06 GMT

It seems the issue is still there with modem fw. 1.3.4

after a certain number of connects/disconnects the modem is not able to connect at all, even after waiting for hours and trying again and agian with a few seconds/minutes gap in between. A hard power reset fixes the issue right away.

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

Didrik Rokhaug — Wed, 20 Apr 2022 15:53:31 GMT

Hi Sashi,

As I said in my previous reply to GJSea, I will need a modem trace to be able to look further into the cause of the lock ups you are seeing.

Please also include which SDK and modem FW versions you are using, as they might not be the same as it was a year ago.

Best regards,

Didrik

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

Sashi — Mon, 18 Apr 2022 21:29:47 GMT

I tried using sys_power(1) as well as toggling the with

AT+CFUN=4 and

AT+CFUN=1

I do have a theory that perhaps the sim card gets to a weird state, and the resetting the sim card is needed with a

AT+CFUN=4 command. but I have not idea what the modem code is doing, so just taking stabs into the black box and hoping for a good result.

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

GJSea — Mon, 18 Apr 2022 20:50:55 GMT

Agreed, there's a definite flaw in the system if we're both seeing this. Didrik Rokhaug any more ideas what might be going on in our situations, whereby a power cycle immediately addresses the connectivity issues the SOC experiences?

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

Sashi — Thu, 14 Apr 2022 23:48:56 GMT

So We are seeing something similar. where a sys_reboot does not recover the device. But simply cutting power and re powering restores the device instantly.

The device can stay connected for say 10-12 hours, but if there is an issue, the device can sys_reboot all day long after timing out over and over again. But the second the device is power cycled it connects and starts working again like nothing is wrong.

There must be another command that allows your to restore the modem state the same as coming out of a power cycle.

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

Didrik Rokhaug — Wed, 19 May 2021 13:35:23 GMT

Hi, and sorry for the late reply.

The modem should be reset in a similar fashion when doing a soft reset as when doing a power reset. The only exception I have been able to find would be the RAM.

Unfortunately, without a modem trace, we are not able to say anything more about the cause of this problem. Are you able to reproduce this in a lab, or set up a device with modem tracing enabled in the field?

Best regards,

Didrik

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

GJSea — Thu, 06 May 2021 16:30:48 GMT

These devices are deployed in public spaces in the field so modem trace capture isn't possible. However we have advanced flash storage logging capability so when the device does finally connect to the cloud, we get an upload of the application level firmware activity.

For a given device, Signal strength around -80 dBm.

- mqtt_connect() underlying socket connect blocks for an unacceptably long time (we cant have the CPU be at non PSM power state for too long otherwise the battery levels will drop off), so after an application timeout period such as 120 seconds we sys_reboot the device.

- We then sleep for 60m in case it is a cellular network or cloud outage.

- Try connecting again, LTE network acquisition successful, mqtt_connect to the cloud backend, socket connection block, so sys_reboot.

- We're then in a loop of socket connect blocks and reboots.

- Finally someone goes to the device and powers it off and on from the enclosure exterior with a magnet and hall sensor switch, and lo and behold the device connects instantly to the network and the socket connect succeeds to the cloud backend. The device works normally for some period again (say for 10 hours at 10 connections per hour), then ends up socket connect blocking again.

So my question is what does the power cycling do in terms of resetting 'something' that clears the indefinite socket connect blocking attempts? Dozens of other devices are in the same neighborhood so area cellular connectivity and cloud backend aren't a factor, perhaps specific tower connectivity is.

What would really be handy is getting a debug stream of say the last 20 events from modem AT+ calls, otherwise deployed modem diagnosis simply isn't possible,

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

Didrik Rokhaug — Thu, 06 May 2021 15:15:35 GMT

sys_reboot should do a soft reset of the modem, as well as of the application.

The modem team would like a modem trace to investigate what happens both during your 'DNS/cellular connectivity issues', and during the reset.

Could you capture a modem trace for them to analyze?

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

GJSea — Wed, 05 May 2021 17:51:33 GMT

I'm using modem firmware 1.2.2. I'm not doing anything specific to turn off the modem, is there an AT+ command way to reboot it? Does sys_reboot reboot the modem or sys_reboot only reboot the firmware running on the program side of the CPU?

Thanks!

RE: Is there a way to truly hard reset the nRF9160 without power cycling?

Didrik Rokhaug — Wed, 05 May 2021 14:01:25 GMT

Hi,

I have forwarded your question to our modem team.

What modem firmware version are you using?

How do you turn off the modem before the reset?

If you turn it off with AT+CFUN=0, it will store the current network parameters to flash, to speed up future connection attempts.

Best regards,

Didrik