AT commands stopped working in 1.2.1 FW

[fastfox]

Hi,

I've been using XMONITOR command to check some radio parameters. ATM, I am checking those once/minute, right before requesting power save mode from modem. After updating modem FW to 1.2.1 (from 1.2.0), command stops working after ~6 minutes of operation

<err> at_cmd: Failed to send AT command (err:22)

Also power save mode stops working

00> [00:14:05.393,615] <err> lte_lc: Could not set CEREG, error: -22
00> [00:14:05.393,615] <err> modem_if: Error getting PSM: -22 Errno: 2

[Øyvind]

Hello, 

What version of NCS are you using? If using master, can you try with NCS v1.3.0 or if using v1.3.0 try master. Do you get similar response when using AT Client? 

Thank you!

Kind regards,
Øyvind

[fastfox]

I am using 1.3.0. I have a custom board and don't have a serial connection to the modem, so I can't  really use AT client. I wonder if one could use serial over SWD somehow?

I narrowed the problem down so that it fails only when I have two network connections ongoing at the same time. So it could be that the number of open sockets is somehow related.

[Øyvind]

Error 22 is EINVAL. Please be aware that XMONITOR has been updated, according to the release history. Please ensure that you are using the command correctly according to the updated documentation.

Do you have an external debugger to use? If so you can use RTT to view log output. 

[fastfox]

Banging my head on this one for a change.

As I said before AT interface only breaks if I have two active socket connections ongoing at the same time. I have LWM2M(DTLS) for production and for RnD purposes I also have MQTT(TLS) connection sometimes active at the same time. I can only see this error happening when both connections are active

Also. If I enable debug logs from AT interface:

CONFIG_AT_CMD_LOG_LEVEL_DBG=y

CONFIG_AT_HOST_LOG_LEVEL_DBG=y

CONFIG_AT_NOTIF_LOG_LEVEL_DBG=y

I can never reproduce the problem. So it might have something to do with things happening too fast/in wrong order or something.

Only recovery seems to be a reboot. If I see this -22 once, no AT command will ever succeed after that.

Not much to work with, I understand, but just wanted to let you know. Luckily this is not a show stopper as in production I won't be having these multiple connections 

[Øyvind]

Please provide a modem trace for us to see what is going when you send command.

Thanks! 

Kind regards,
Øyvind