Pristine WP7702 keeps restarting every few hours

IoT Modules WP Series
1

I have a WP7702 on a MangoH Reb board that keeps restarting with no suspicious log messages on the console. With intervals from 20 minutes to hours it just restarts out of the blue.

I have just reflashed it with the latest official firmware but the behaviour is the same.

As can be seen from the console dump below, it just reboots straight out of the blue from the login: prompt with no user activity since the prevous reboot.

Any hints?


Starting Dropbear SSH server: dropbear.
run_getty.sh: ttyHSL1 reserved for CONSOLE

Poky (Yocto Project Reference Distro) 2.5.3 swi-mdm9x28-wp /dev/ttyHSL1

swi-mdm9x28-wp login: Android Bootloader - UART_DM Initialized!!!
[10] Qseecom Init Done in Appsbl version is 0x405000
[10] secure app region addr=0x87900000 size=0x280000[20] TZ App region notif returned with status:0 addr:87900000 size:2621440
[20] TZ App log region register returned with status:0 addr:82681000 size:4096
[30] Qseecom TZ Init Done in Appsbl
[30] ERROR: No devinfo partition found
`
`
2

Does problem happen at+cun=0
Does problem happen if without sim card?

3

Yes, the SIM slot is empty.

How do I get the value of at+cun? What does it do?
It is not documented in AT command reference

root@swi-mdm9x28-wp:~# microcom /dev/ttyAT
at
OK
at+cun?
ERROR
at+cun=?
ERROR
at+cun=
ERROR
4

sorry, typo , should be AT+CFUN:

https://m2msupport.net/m2msupport/atcfun-set-phone-functionality/

5

Ah good. Current value seems to be “1”

at+cfun?
+CFUN: 1

OK
at+cfun=?
+CFUN: (0-1,4-7),(0-1)

OK
6

you can try to stop the RF functionality by AT+CFUN=0.

7

OK. Thanks.
I will report back here with the results.