RM520N-GL and SK Telecom

Hi, we are having issue with RM520N-GL module when trying to register in SK Telecom network with SK Telecom SIM card (which works fine when installed to some other UE link mobile phone). It seems that module itself sees the operator’s network but does not register in it automatically. Moreover if I’m trying to register in operators network manually using command AT+COPS=1,2,"45005",7 after some delay I get error +CME ERROR: 30 (+CME ERROR: no network service).

I’ve tried several firmwares and some of them be able to connect using UMTS access technology and some of them cannot connect at all:

  • RM520NGLAAR03A01M4G_01.202.01.202, RM520NGLAAR03A02M4GA, RM520NGLAAR03A03M4G - cannot register at all
  • RM520NGLAAR01A07M4G_01.201.01.201, RM520NGLAAR01A07M4G_01.203.01.203, RM520NGLAAR01A08M4G - can only register in 3G (UMTS) network.

How can I understand whats going wrong here?

Dear @Kamil_Zaripov1
Which rat did register when the SIM card with mobile phone? Lte or NAS?
Pease help to execute the AT commands below and share the response:
ACFUN?
AT+CSQ
AT+QNWPREFFG=“mode_pref”
AT+QMBNCFG=“list”
AT+QNWPREFCFG=“gw_band”
AT+QNWPREFCFG=“lte_band”
AT+QNWPREFCFG=“nsa_nr5g_band”
AT+QNWPREFCFG=“nr5g_band”
AT+QNWPREFCFG=“policy_band”
AT+QNWPREFCFG= “rat_acq_order”
AT+QNWPREFCFG=“nr5g_disable_mode”

Which rat did register when the SIM card with mobile phone? Lte or NAS?

We’ve tested and most probably it works on 5G NR, either 5G NSA or 5G SA. At least phone writes 5G label on top right part of the screen.

Pease help to execute the AT commands below and share the response:

AT+CFUN?
+CFUN: 1

OK
AT+CSQ
+CSQ: 25,99

OK
AT+QNWPREFCFG="mode_pref"
+QNWPREFCFG: "mode_pref",AUTO

OK
AT+QMBNCFG="list"
+QMBNCFG: "List",0,1,1,"Commercial-SKT",0x0A01270A,202111051
+QMBNCFG: "List",1,0,0,"TEF_Spain_Commercial",0x0A010C00,202302071
+QMBNCFG: "List",2,0,0,"ROW_Generic_3GPP_PTCRB_GCF",0x0A01FF09,202205261
+QMBNCFG: "List",3,0,0,"FirstNet",0x0A015300,202206171
+QMBNCFG: "List",4,0,0,"Rogers_Canada",0x0A014800,202303141
+QMBNCFG: "List",5,0,0,"Bell_Canada",0x0A014700,202111051
+QMBNCFG: "List",6,0,0,"Telus_Canada",0x0A014900,202112271
+QMBNCFG: "List",7,0,0,"Commercial-Sprint",0x0A010204,202111051
+QMBNCFG: "List",8,0,0,"Commercial-TMO",0x0A01050F,202303091
+QMBNCFG: "List",9,0,0,"VoLTE-ATT",0x0A010335,202208211
+QMBNCFG: "List",10,0,0,"CDMAless_Private-Verizon",0x0A01FD28,202305082
+QMBNCFG: "List",11,0,0,"CDMAless-Verizon",0x0A010126,202209281
+QMBNCFG: "List",12,0,0,"Telia_Sweden",0x0A012400,202111051
+QMBNCFG: "List",13,0,0,"TIM_Italy_Commercial",0x0A012B00,202111051
+QMBNCFG: "List",14,0,0,"France-Commercial-Orange",0x0A010B21,202111051
+QMBNCFG: "List",15,0,0,"Commercial-DT-VOLTE",0x0A011F1F,202206131
+QMBNCFG: "List",16,0,0,"Germany-VoLTE-Vodafone",0x0A010449,202111051
+QMBNCFG: "List",17,0,0,"UK-VoLTE-Vodafone",0x0A010426,202111051
+QMBNCFG: "List",18,0,0,"Commercial-EE",0x0A01220B,202111051
+QMBNCFG: "List",19,0,0,"Optus_Australia_Commercial",0x0A014400,202111051
+QMBNCFG: "List",20,0,0,"Telstra_Australia_Commercial",0x0A010F00,202304251
+QMBNCFG: "List",21,0,0,"Commercial-LGU",0x0A012608,202111051
+QMBNCFG: "List",22,0,0,"Commercial-KT",0x0A01280B,202304191
+QMBNCFG: "List",23,0,0,"Commercial-Reliance",0x0A011B0C,202210211
+QMBNCFG: "List",24,0,0,"Commercial-SBM",0x0A011C0B,202111051
+QMBNCFG: "List",25,0,0,"Commercial-KDDI",0x0A010709,202111051
+QMBNCFG: "List",26,0,0,"Commercial-DCM",0x0A010D0D,202208151
+QMBNCFG: "List",27,0,0,"VoLTE-CU",0x0A011561,202204211
+QMBNCFG: "List",28,0,0,"VoLTE_OPNMKT_CT",0x0A0113E0,202204211
+QMBNCFG: "List",29,0,0,"Volte_OpenMkt-Commercial-CMCC",0x0A012010,202212151
+QMBNCFG: "List",30,0,0,"ROW_Commercial",0x0A010809,202305221

OK
AT+QNWPREFCFG="gw_band"
+QNWPREFCFG: "gw_band",1:2:4:5:8:19

OK
AT+QNWPREFCFG="lte_band"
+QNWPREFCFG: "lte_band",1:2:3:4:5:7:8:12:13:14:17:18:19:20:25:26:28:29:30:32:34:38:39:40:41:42:43:46:48:66:71

OK
AT+QNWPREFCFG="nsa_nr5g_band"
+QNWPREFCFG: "nsa_nr5g_band",1:2:3:5:7:8:12:13:14:18:20:25:26:28:29:30:38:40:41:48:66:70:71:75:76:77:78:79

OK
AT+QNWPREFCFG="nr5g_band"
+QNWPREFCFG: "nr5g_band",0

OK
AT+QNWPREFCFG="nr5g_band"
+QNWPREFCFG: "nr5g_band",0

OK
AT+QNWPREFCFG="policy_band"
+QNWPREFCFG: "gw_band",1:2:4:5:6:8:19
+QNWPREFCFG: "lte_band",1:2:3:4:5:7:8:12:13:14:17:18:19:20:25:26:28:29:30:32:34:38:39:40:41:42:43:46:48:66:71
+QNWPREFCFG: "nsa_nr5g_band",1:2:3:5:7:8:12:13:14:18:20:25:26:28:29:30:38:40:41:48:66:70:71:75:76:77:78:79
+QNWPREFCFG: "nr5g_band",1:2:3:5:7:8:12:13:14:18:20:25:26:28:29:30:38:40:41:48:66:70:71:75:76:77:78:79

OK
AT+QNWPREFCFG="rat_acq_order"
+QNWPREFCFG: "rat_order_pref",NR5G:LTE:WCDMA

OK
AT+QNWPREFCFG="nr5g_disable_mode"
+QNWPREFCFG: "nr5g_disable_mode",1

OK

AT commands are performed on module with RM520NGLAAR01A08M4G firmware.

@silvia Do I need to provide any other information?

Install an apk like celluar-Z to show the cellular tech that the phone registerred with.

Install an apk like celluar-Z to show the cellular tech that the phone registerred with.

Well, I need to ask to do it a guy at the other time zone in his personal phone and it can be complicated.

The thing is the phone:

  • register in operators network
  • does not use UMTS RAT

and the RM520N-GL module:

  • depending on firmware register or refuse to register in operators network
  • use UMTS RAT in best case

Dear @Kamil_Zaripov1
Please execute
AT+QNWPREFCFG=“nr5g_disable_mode”,0
AT+QENG=“servingcell”
AT+QENG=“neighbourcell”

Please execute
AT+QNWPREFCFG=“nr5g_disable_mode”,0
AT+QENG=“servingcell”
AT+QENG=“neighbourcell”

AT+QNWPREFCFG="nr5g_disable_mode",0

OK
AT+QENG="servingcell"
+QENG: "servingcell","SEARCH"

OK
AT+QENG="neighbourcell"
+QENG: "neighbourcell intra","LTE",1350,388,-9,-69,-39,-,58,7,62,18,62
+QENG: "neighbourcell intra","LTE",1350,444,-17,-76,-47,-,51,7,62,18,62
+QENG: "neighbourcell intra","LTE",1350,438,-20,-76,-47,-,51,7,62,18,62
+QENG: "neighbourcell inter","LTE",2500,388,-12,-70,-50,-,58,5,8,8
+QENG: "neighbourcell inter","LTE",2500,74,-12,-70,-50,-,58,5,8,8
+QENG: "neighbourcell inter","LTE",2500,444,-18,-76,-50,-,58,5,8,8
+QENG: "neighbourcell inter","LTE",275,388,-11,-82,-59,-,51,4,26,26
+QENG: "neighbourcell inter","LTE",275,243,-20,-87,-59,-,51,4,26,26
+QENG: "neighbourcell inter","LTE",2850,388,-9,-75,-58,-,51,3,30,30
+QENG: "neighbourcell inter","LTE",2850,243,-18,-88,-58,-,51,3,30,30
+QENG: "neighbourcell inter","LTE",3200,388,-10,-83,-64,-,0,2,30,30
+QENG: "neighbourcell inter","LTE",9410,120,-8,-86,-70,-,0,1,30,30

AT commands are performed on module with RM520NGLAAR01A08M4G firmware.

Dear @Kamil_Zaripov1
After execute AT+QNWPREFCFG=“nr5g_disable_mode”,0, it still can’t register, right?
Please try to execute the AT commands below:
AT+QMBNCFG=“deactivate”
AT+QMBNCFG=“autosel”,0
AT+QMBNCFG=“select”,“ROW_Commercial”
AT+CFUN=1,1
AT+QMBNCFG=“List”

Wait more time and check whether register or not.

It register, but only in 3g (with RM520NGLAAR01A08M4G firmware).

Yes, after manually selecting ROW_Commercial modem connects using LTE RAT:

AT+QMBNCFG="deactivate"
OK
AT+QMBNCFG="autosel",0
OK
AT+QMBNCFG="select","ROW_Commercial"
OK
AT+CFUN=1,1
OK

# here modem disonnects from USB, and connects back

RDY

+CFUN: 1

+CPIN: READY

+QUSIM: 1

+QIND: SMS DONE

+QIND: PB DONE

AT+QMBNCFG="List"
+QMBNCFG: "List",0,1,1,"ROW_Commercial",0x0A010809,202305221
+QMBNCFG: "List",1,0,0,"Commercial-SKT",0x0A01270A,202111051
+QMBNCFG: "List",2,0,0,"TEF_Spain_Commercial",0x0A010C00,202302071
+QMBNCFG: "List",3,0,0,"ROW_Generic_3GPP_PTCRB_GCF",0x0A01FF09,202205261
+QMBNCFG: "List",4,0,0,"FirstNet",0x0A015300,202206171
+QMBNCFG: "List",5,0,0,"Rogers_Canada",0x0A014800,202303141
+QMBNCFG: "List",6,0,0,"Bell_Canada",0x0A014700,202111051
+QMBNCFG: "List",7,0,0,"Telus_Canada",0x0A014900,202112271
+QMBNCFG: "List",8,0,0,"Commercial-Sprint",0x0A010204,202111051
+QMBNCFG: "List",9,0,0,"Commercial-TMO",0x0A01050F,202303091
+QMBNCFG: "List",10,0,0,"VoLTE-ATT",0x0A010335,202208211
+QMBNCFG: "List",11,0,0,"CDMAless_Private-Verizon",0x0A01FD28,202305082
+QMBNCFG: "List",12,0,0,"CDMAless-Verizon",0x0A010126,202209281
+QMBNCFG: "List",13,0,0,"Telia_Sweden",0x0A012400,202111051
+QMBNCFG: "List",14,0,0,"TIM_Italy_Commercial",0x0A012B00,202111051
+QMBNCFG: "List",15,0,0,"France-Commercial-Orange",0x0A010B21,202111051
+QMBNCFG: "List",16,0,0,"Commercial-DT-VOLTE",0x0A011F1F,202206131
+QMBNCFG: "List",17,0,0,"Germany-VoLTE-Vodafone",0x0A010449,202111051
+QMBNCFG: "List",18,0,0,"UK-VoLTE-Vodafone",0x0A010426,202111051
+QMBNCFG: "List",19,0,0,"Commercial-EE",0x0A01220B,202111051
+QMBNCFG: "List",20,0,0,"Optus_Australia_Commercial",0x0A014400,202111051
+QMBNCFG: "List",21,0,0,"Telstra_Australia_Commercial",0x0A010F00,202304251
+QMBNCFG: "List",22,0,0,"Commercial-LGU",0x0A012608,202111051
+QMBNCFG: "List",23,0,0,"Commercial-KT",0x0A01280B,202304191
+QMBNCFG: "List",24,0,0,"Commercial-Reliance",0x0A011B0C,202210211
+QMBNCFG: "List",25,0,0,"Commercial-SBM",0x0A011C0B,202111051
+QMBNCFG: "List",26,0,0,"Commercial-KDDI",0x0A010709,202111051
+QMBNCFG: "List",27,0,0,"Commercial-DCM",0x0A010D0D,202208151
+QMBNCFG: "List",28,0,0,"VoLTE-CU",0x0A011561,202204211
+QMBNCFG: "List",29,0,0,"VoLTE_OPNMKT_CT",0x0A0113E0,202204211
+QMBNCFG: "List",30,0,0,"Volte_OpenMkt-Commercial-CMCC",0x0A012010,202212151

OK
AT+COPS?
+COPS: 0,0,"SKTelecom",7

OK

So what is the solution for this issue? Users should manually configure MBN for each mobile operator?

@silvia So should I wait for new firmware or I should switch to ROW_Commertial on all modules that work with SKT?

@silvia Is there any updates?

Dear @Kamil_Zaripov1
Sorry for the late.
Actually, for the MBN file, it is hard to say the configurations in module fit the operator.
ROW_Commertial is a common one.
Currently, you can change mbn manually to solve your problem.