Switching COPS mode while registerd to a network | Telit Cinterion IoT Developer Community
September 4, 2018 - 4:30pm, 4409 views
Hello
I have a question regarding the AHS3-W:
The modem is configured for automatic operator selection AT+COPS=0
There can be situations where the modem is registered to a roaming network PLMN1 and we want to force the modem to register to another roaming network PLMN2.
I can do this by deregistering using AT+COPS=2 and using manual registration AT+COPS=1,2,"PLMN2"
After the modem has registered to the new roaming network PLMN2, the modem is now in manual operator mode.
At this time I like to bring the modem back to automatic mode WITHOUT deregistration of the network PLMN2 that I have selected manually.
If I would use AT+COPS=0, would the modem remain in PLMN2 or would AT+COPS=0 force the modem to register to another network which could be PLMN1 again?
If it would go back to PLMN1, would there be any other way to stay registered in PLMN2 but have automatic mode turned on so that automatic network selection takes place as soon as PLMN2 gets lost?
Regards
Franz
Hi
If you using AT+COPS=1,2 then you need to write "Numeric format of . This is the Location Area Identification (LAI) number, which consists of the 3-digit Mobile Country Code (MCC) plus the 2- or 3-digit Mobile Network Code (MNC)."
You can also try another mode value "4". It means: "Automatic / manual selection; if manual selection fails, automatic mode (=0) is entered ( field will be present)."
In my side I've done some tests, and AT+COPS=0 does deregister my moddule from network and register automatic to the other one.
If you can, please do some tests using AT+CREG=2. This set value can show you all network URCs.
Regards
Krzysztof
Thank you.
AT+COPS=4,2,"PLMN2" will not help because after the module has registered to PLMN2 it remains in manual mode and if PLMN2 gets lost the module won't automatically register to any other network.
If AT+COPS=0 will also not help, is there any other way to solve my problem?
What about modifying the preferred operator list to force AT+COPS=0 to register to PLMN2 only like:
module registered to PLMN1
AT+COPS=2 ..... deregister from PLMN1
AT+COPS=1,2,"PLMN2" ........ module registered to PLMN2
clear preferred operator list
AT+CPOL=1,2,"PLMN2" ........ just add PLMN2 to POL, no other PLMN in list
AT+COPS=0 ......... module deregisteres from PLMN2 but registers back to PLMN2 because its the preferred operator
Would that work?
Unfortunately I don't have the ability to test it.
Any other ideas, perhaps using AT+CRSM to modify some other files with PLMN entries?
Regards
Franz
Hi
Sorry, my bad. AT+COPS=4,2,"PLMN2" works as you described.
AT+CPOL=1,2,"PLMN2" add PLMN2 to preffered list but your network provider can change your POL list without inform you about it. If everything will be okay it should connect to your preffered roaming network after AT+COPS=0 and choosing it. To work with CPOL there is need to set up AT+CPLS.
My other idea is to write AT+COPS=? command and check if there is your PLMN and if it is, then try to connect to them using AT+COPS=1...
If your module is in one place it will try to attach to the previus PLMN network. But if it moves CPOL or COPS=? is a good way. It should works but as i mentioned before, due to your network provider it can change your prefered list.
Regards
Krzysztof
Thanks again.
One more question: If AT+COPS=0 is set and the module is registered to the best network available and then I invoke AT+COPS=0 again, would the module first deregister and then register again to the same network or would it just do nothing and remain registered on its choosen network?
Regards
Franz
Hi
When you are register in some network (manual or automatic) in AHS3-W after sending AT+COPS=0 module will send "Routing Area Update". It means it won't deregister from your network only change for better technology. E.g.: you are in 2G. AT+COPS=0. Module sends to network "Routing Area Update". And if there will your home network in 3G it will change to it while you are still connected to the network. If you are in 3G it will stay in it. In automatic mode module will first try to attempt to connect to home operator. If home network is not found AHS3-W goes on searching permitted operator to register in.
Regards
Krzysztof