Network selection issue on PHS8-P | Telit Cinterion IoT Developer Community
August 29, 2016 - 12:29pm, 4133 views
Hi.
We are using PHx8 modules in most of our products.
Recently we discovered a strange problem regarding network selection.
Module version information:
ati1
Cinterion
PHS8-P
REVISION 03.001
A-REVISION 01.001.07
OK
The problem that we are seeing is that the module does NOT select any RAT > 0, it is only registring to GSM networks. But I know for a fact that there are ULTRAN networks available. Note that below I have produced some output from a single device, we have more then 30 devices that behave in the same way.
Initial network scan when the device is only connecting to GSM:
at+cops=2
OK
at+creg?
+CREG: 0,0
OK
at^snmon="iun
ERROR
at^snmon="ins",2
^SNMON: "INS",0,1,3,"410C","2AFC","24024",35,31,"-47"
^SNMON: "INS",0,1,3,"2BEA","2AFC","24024",39,17,"-79"
^SNMON: "INS",0,1,3,"3F86","2AFC","24024",66,15,"-83"
^SNMON: "INS",0,1,3,"410D","2AFC","24024",43,14,"-86"
^SNMON: "INS",0,1,3,"1583","2338","24001",90,14,"-87"
^SNMON: "INS",0,1,3,"406B","2AFC","24024",49,13,"-90"
^SNMON: "INS",0,1,3,"16DD","2338","24001",78,11,"-92"
^SNMON: "INS",0,1,3,"2BE9","2AFC","24024",53,10,"-94"
^SNMON: "INS",0,1,3,"3EC9","2AF9","24024",64,8,"-97"
^SNMON: "INS",0,1,3,"172A","2338","24001",93,7,"-100"
^SNMON: "INS",0,1,3,"E4B9","2338","24001",79,6,"-101"
^SNMON: "INS",0,1,3,"E985","2338","24001",80,7,"-101"
^SNMON: "INS",0,2
^SNMON: "INS",0,4
^SNMON: "INS",0,8
^SNMON: "INS",0,16
^SNMON: "INS",0,32
^SNMON: "INS",0,64
^SNMON: "INS",0,128
^SNMON: "INS",0,256
OK
But forcing the device to select a ULTRAN network (without changing location) gives me following output:
at+cops=1,2,24001,2
OK
at+cops?
+COPS: 1,2,"24001",2
OK
at+csq
+CSQ: 26,99
OK
at+csq
+CSQ: 26,99
OK
at^smoni
^SMONI: 3G,10836,205,-4.0,-59,240,01,0073,073CB0E,32,55,NOCONN
OK
at^snmon="ins",2
^SNMON: "INS",0,1,3,"410C","2AFC","24024",35,31,"-48"
^SNMON: "INS",0,16,2,"001364C6","0186","24008",10638,18,"-77",332
^SNMON: "INS",0,1,3,"2BEA","2AFC","24024",39,17,"-80"
^SNMON: "INS",0,16,2,"0013C862","0186","24008",10563,16,"-81",332
^SNMON: "INS",0,16,2,"0013C85F","0186","24008",10613,15,"-84",332
^SNMON: "INS",0,1,3,"3F86","2AFC","24024",66,15,"-84"
^SNMON: "INS",0,16,2,"0013C85C","0186","24008",10588,16,"-85",332
^SNMON: "INS",0,1,3,"410D","2AFC","24024",43,15,"-86"
^SNMON: "INS",0,1,3,"1583","2338","24001",90,14,"-86"
^SNMON: "INS",0,1,3,"406B","2AFC","24024",49,13,"-89"
^SNMON: "INS",0,1,3,"410B","2AFC","24024",63,12,"-90"
^SNMON: "INS",0,1,3,"271D","2AF9","24024",41,12,"-90"
^SNMON: "INS",0,1,3,"16B0","2338","24001",87,13,"-91"
^SNMON: "INS",0,1,3,"271B","2AF9","24024",58,12,"-91"
^SNMON: "INS",0,1,3,"16DD","2338","24001",78,12,"-94"
^SNMON: "INS",0,1,3,"2829","2AF9","24024",74,10,"-95"
^SNMON: "INS",0,16,2,"0013B988","0186","24008",10613,9,"-95",478
^SNMON: "INS",0,1,3,"3F87","2AFC","24024",57,9,"-96"
^SNMON: "INS",0,1,3,"1400","2338","24001",85,9,"-96"
^SNMON: "INS",0,2,3,"3ADF","2338","24001",676,9,"-97"
^SNMON: "INS",0,1,3,"172A","2338","24001",93,7,"-99"
^SNMON: "INS",0,128,2,"003C8549","1234","24001",3084,7,"-100",440
^SNMON: "INS",0,1,3,"E7EB","10DC","24001",84,7,"-100"
^SNMON: "INS",0,128,2,"003C8509","1234","24001",3084,6,"-101",49
^SNMON: "INS",0,1,3,"E985","2338","24001",80,7,"-101"
^SNMON: "INS",0,128,2,"003C9E1F","1234","24001",3084,5,"-104",62
^SNMON: "INS",0,4
^SNMON: "INS",0,8
^SNMON: "INS",0,32
^SNMON: "INS",0,64
^SNMON: "INS",0,256
Now all of sudden it does see ULTRAN networks? Why did it not choose one before, or even see one?
Hopefully someone here can give me some insight.
Also please tell me if there any more information that could be usefull, I have access to a device and can easiliy run some more AT commands.
Best Regards
Mirza
Hello,
If it was working before there must have been something that has changed - network operator, location, configuration, firmware version?
Have you tried to set AT+COPS=0 command to make sure that automatic RAT selection is used? Please paste AT^SCFG? output.
Have you tried other network provider?
Regards,
Bartłomiej
I have no documented behaviour that it has ever worked on this firmware revision. We just have not seen it before.
Every modem startup we run AT+COPS=0,2, which should clear any previous RAT selection used and switch to automatic.
AT^SCFG? output below:
at^scfg?
^SCFG: "Audio/Loop","0"
^SCFG: "Call/ECC","0"
^SCFG: "Call/Speech/Codec","0"
^SCFG: "GPRS/Auth","2"
^SCFG: "GPRS/AutoAttach","disabled"
^SCFG: "GPRS/MaxDataRate/HSDPA","0"
^SCFG: "GPRS/MaxDataRate/HSUPA","0"
^SCFG: "Ident/Manufacturer","Cinterion"
^SCFG: "Ident/Product","PHS8-P"
^SCFG: "MEopMode/Airplane","off"
^SCFG: "MEopMode/CregRoam","0"
^SCFG: "MEopMode/CFUN","0","1"
^SCFG: "MEopMode/PowerMgmt/LCI","disabled"
^SCFG: "MEopMode/PowerMgmt/VExt","high"
^SCFG: "MEopMode/PwrSave","enabled","0","50"
^SCFG: "MEopMode/RingOnData","off"
^SCFG: "MEopMode/RingUrcOnCall","on"
^SCFG: "MEShutdown/OnIgnition","on"
^SCFG: "Radio/Band","511"
^SCFG: "Radio/Mtpl","0"
^SCFG: "Radio/NWSM","0"
^SCFG: "Radio/OutputPowerReduction","8"
^SCFG: "Serial/USB/DDD","0","0","0409","1E2D","0053","Cinterion","PH8",""
^SCFG: "Serial/USB/DeviceClass/RmNet",""
^SCFG: "URC/DstIfc","app"
^SCFG: "URC/Datamode/Ringline","on"
^SCFG: "URC/Ringline","local"
^SCFG: "URC/Ringline/ActiveTime","1"
OK
My colleagues have tried different network provides with the same result. But I will try again. Should be noted that our default network provider is mostly roaming, the provider is from France, we are in Sweden. But as I said will try with a different network provider, this time a local one.
Also one strange behaviour that I have observered is that once I have forced it to a ULTRAN network with manuell selection with AT+COPS, it seems to stay connected to the ULTRAN network even if a restart the modem. What could be reason for that?
Best Regards
Mirza
Hello,
According to documentation values 0 and 1 of mode parameter are stored in the non-volatile memory of the PHS8-P.
Have you tried AT+COPS=? - does it list all available networks or also 2G only? I don't know at the moment why AT^SNMON behaves like that. COPS should list all.
Besides AT^SNMON reply have you done more tests that prove that the module only registers to 2G? How about if you use a data transmission?
In AT^SCFG command output it seems that all bands are selected. You could limit the bands to 3G only and verify if the module registers automatically to 3G. Or change the rat to 3G IN COPS command for test.
Best regards,
Bartłomiej
Hi,
Yes, I tried this out yesterday. As you can see below, at+cops=? lists the ULTRAN networks but it just does not connect to them.
at+cops?
+COPS: 0,2,"24024",0
OK
at+cops=?
+COPS: (1,"Tele2 SE","Tele2 SE","24007",2),(1,"TELIA S","TELIA","24001",0),(1,"TELIA S","TELIA","24001",2),(2,"Sweden Mobile","MobileS","24024",0),(1,"3 SE","3 SE","24002",2),(1,"Telenor SE","TelenorS","24008",2),,(0,1,2,3,4),(0,1,2,90,91)
OK
at+cops?
+COPS: 0,2,"24024",0
OK
at+cops?
+COPS: 0,2,"24024",0
Changing the RAT in COPS to 3G does force it to connect to a 3G network and there is no issues with the 3G network once connected this way. But I should not have to force to 3G manually, it should be able to automaticly do this since they are available.
Best Regards
Mirza
We have also done some tests and there's the same situation regarding AT^SNMON - when the module is deregistered from the network SNMON does not show all available cells (and only shows 2G). When registered to 3G it shows much more (including 3G).
It is better to use AT+COPS to check available networks which always show all.
But in our case the module has registered to 3G in automatic mode.
Here's the log:
ati1
Cinterion
PHS8-P
REVISION 03.001
A-REVISION 01.000.01
OK
at+cops=0
OK
at+cops?
+COPS: 0,0,"Plus",2
OK
at+cops=2
OK
at+cops=?
+COPS: (0,"T-Mobile.pl","TM
PL","26002",0),(0,"Play","Play","26006",0),(0,"Orange
PL","Orange","26003",0),(0,"Plus","Plus","26001",0),(0,"T-Mobile.pl","TM
PL","26002",2),(0,"Plus","Plus","26001",2),(0,"Play","Play","26006",2),(0,"Orange
PL","Orange","26003",2),,(0,1,2,3,4),(0,1,2,90,91)
OK
at^snmon="INS",2
^SNMON: "INS",0,2,3,"98A6","0BDF","26006",677,11,"-92"
^SNMON: "INS",0,1,3,"8767","7D03","26001",13,8,"-98"
^SNMON: "INS",0,1,3,"8765","7D03","26001",40,6,"-101"
^SNMON: "INS",0,4
^SNMON: "INS",0,8
^SNMON: "INS",0,16
^SNMON: "INS",0,32
^SNMON: "INS",0,64
^SNMON: "INS",0,128
^SNMON: "INS",0,256
OK
at+cops=0
OK
at+cops?
+COPS: 0,0,"Plus",2
OK
at^snmon="INS",2
^SNMON: "INS",0,2,3,"FCFE","E182","26002",705,12,"-92"
^SNMON: "INS",0,2,3,"98A6","0BDF","26006",677,11,"-93"
^SNMON: "INS",0,2,3,"98A5","0BDF","26006",672,10,"-94"
^SNMON: "INS",0,1,3,"FCC2","E182","26003",111,9,"-96"
^SNMON: "INS",0,1,3,"FCF4","E182","26002",23,9,"-97"
^SNMON: "INS",0,16,2,"02C5FD1C","E182","26002",10688,7,"-99",253
^SNMON: "INS",0,1,3,"8767","7D03","26001",13,6,"-102"
^SNMON: "INS",0,1,3,"8765","7D03","26001",40,5,"-103"
^SNMON: "INS",0,1,3,"FCF2","E182","26002",25,5,"-103"
^SNMON: "INS",0,2,3,"FCFC","E182","26002",701,5,"-104"
^SNMON: "INS",0,16,2,"02C5FD12","E182","26002",10663,2,"-112",253
^SNMON: "INS",0,16,2,"0C80BF5F","7D03","26001",10737,0,"-115",313
^SNMON: "INS",0,4
^SNMON: "INS",0,8
^SNMON: "INS",0,32
^SNMON: "INS",0,64
^SNMON: "INS",0,128
^SNMON: "INS",0,256
OK
So regarding the automatic network registration to 2G it doesn't seem to be any bug - it might be network or SIM provider dependant (please check with other network provider and other location - the result may be different). If you want 3G only and does not want 2G you have to configure the module appropriately. Otherwise you rely on the automatic mode where you have no influence on the network type that is chosen.
Regards,
Bartłomiej
Hi.
I am not ready to give up on this yet :).
I have tried different SIM and different location, but same issue. It only connects to 2G.
It only connects to 3G if do a at+cops=? followed by a at+cops=0. And once this is done ONCE that device is "fixed", it works as expected from this point and on. The devices I usually have issues with is devices that have been turned off for a long time (months).
Another conern that I have is that I only see RAT=2 as maximum on 03.001 firmware revision. Like you had in your response. On older firmware revisions (2.***) I see both RAT 4 and 6, and I do not experiance any issues with networks selection on the older firmware revision.
Best Regards
Mirza
Hello,
It seems that some logic for network selection has been changed in the release 3.
But you have found an interesting way to force the device to search more than 2G at the beginning.
On the other hand maybe the device that was tuned off for a long time and registers to 2G at first would also switch to 3G after some data transmission activity or not.
Regards,
Bartłomiej