Bug in Q24 modules since 6.57e

Description: unexpected module behaviour, module hangs and restarts on data calls and GPRS for newer OS firmware (since 6.57e - AT+WBHV=7,x command was introduced), if compared with OS version 6.57b. Wrong behaviour is observed in OS versions from 6.57e to 6.57h.

How to reproduce:
Data calls bug. Reflash OS with 6.57g. Set host to make data calls every 30 seconds to random phone numbers. During 2-4 hours you can see module restarting at least once after ATD command. Reflash OS with 6.57b and repeat the entire process. There are no restarts with 6.57b.
GPRS bug. Reflash OS with 6.57g and load OpenAT application compiled with SDK 3.19 which sends data to server with TCP socket every 1 minute (WIP+ADL). You will find that during 2-4 hours module will restart at least once after writing data to socket. Reflash OS with 6.57b and repeat experiment. No restarts this time.

PS: Now why don’t use 6.57b? It has a severe bug of hanging and restarting the module after the CONNECT sequence on a certain type of SIM. We cannot avoid using this type of SIM and now we need the bug above to be fixed ASAP!

About this GPRS bug, you mention. Yes, my Q24 also was victim of random unexpected restarts with 6.57g firmware. But with 6.57h problem disappeared, release notes for this version refer to fixed GPRS error, causing random restarts. “Known bug”?

Hi, I have a modem New Q24 series and using Open AT SDK version 3.22, OS 6.57h, and I got this problems too. My modem reset just after a few wip_write :frowning: (about in 1 minute), which OS version I should use now?
Thanks for help.

Your OS version is OK.
Try to increase your stack size used in OpenAT application.