EC25-E with Volte

Hello.
I purchased LTE gateway (Modem for SMS/CALL) using Quectel EC25-E.

When I try to use it in Korea, I am having a hard time because only the data network using VoLTE is available at the corresponding telecommunication company.

While exploring how to set up SMS sending and VoiceCall using Volte, I failed to write on the forum.

The EC25-E chipset supports Volte,

AT+CREG
AT+CGREG
AT+CFUN
AT+COPS
AT+QMBNCFG
AT+QCFG=“ims”
AT+CGDCONT
AT+CGACT

//I tried the necessary things with the command above, but it failed.

+COPS: (2,“LG U+”,“LG U+”,“45006”,7),(3,“KT”,“KT”,“45008”,2),(3,“450 12”,“450 12”,“45012”,7),(3,“450 30”,“450 30”,“45030”,7),(3,“KOR SK Telecom”,“SKT”,“45005”,2),(3,“KOR SK Telecom”,“SKT”,“45005”,7),(3,“KT”,“KT”,“45008”,7),(0-4),(0-2)

//Using LG U+ 45006 above,

AT+QMBNCFG=“list”

+QMBNCFG: “List”,0,0,0,“ROW_Generic_3GPP”,0x0501081F,202108201
+QMBNCFG: “List”,1,0,0,“Reliance_OpnMkt”,0x05011B38,202003251
+QMBNCFG: “List”,2,0,0,“TW_Mobile_China_VoLTE”,0x0580FB81,202104162
+QMBNCFG: “List”,3,0,0,“Bouygues_France_VoLTE”,0x05800101,201905211
+QMBNCFG: “List”,4,0,0,“Telstra-Commercial_VoLTE”,0x0580079E,202105192
+QMBNCFG: “List”,5,0,0,“Commercial-Smartfren”,0x0501250A,202012291
+QMBNCFG: “List”,6,0,0,“VF_Germany_VoLTE”,0x0502041C,202111041
+QMBNCFG: “List”,7,0,0,“Swis_switzerland_VoLTE_VoWiFi”,0x05011421,201910291
+QMBNCFG: “List”,8,0,0,“TF_Spain_VoLTE”,0x05010CFA,202106171
+QMBNCFG: “List”,9,0,0,“Commercial-DT”,0x05011F1C,202111101
+QMBNCFG: “List”,10,0,0,“Commercial-KT”,0x05012C0D,202108241
+QMBNCFG: “List”,11,0,0,“Commercial-SKT”,0x05012715,202103121
+QMBNCFG: “List”,12,1,1,“Commercial-LGU”,0x05012626,202108241
+QMBNCFG: “List”,13,0,0,“Commercial-Airtel”,0x05011A0A,000000000

+QMBNCFG: “List”,12,1,1,“Commercial-LGU”,0x05012626,202108241

//It’s LG’s commercial network, but I think it’s an Internet phone network.
//Do I need to add MBN list?
//I’m sorry for my poor English
//Next time, I’ll write down the actual input and the result.

Please report the results from the following AT commands:

AT+QCFG="ims"
AT+CGDCONT?
AT+CGPADDR
AT+CEREG=2;+CEREG?;+CEREG=0
AT+CGSMS?
AT$QCPDPIMSCFGE?

+QCFG: “ims”,1,0
OK

+CGDCONT: 1,“IPV4V6”,“internet.lguplus.co.kr”,“0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0”,0,0,0,0
+CGDCONT: 2,“IP”,“internet.lguplus.co.kr”,“0.0.0.0”,0,0,0,0
+CGDCONT: 3,“IPV4V6”,“ims”,“0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0”,0,0,0,0
OK

+CGPADDR: 1,“10.85.16.163”
+CGPADDR: 2,“0.0.0.0”
+CGPADDR: 3,“0.0.0.0,0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0”
OK

OK

+CEREG: 2,1,“616D”,“323B80E”,7
OK

OK

+CGSMS: 1
OK

$QCPDPIMSCFGE: 1 , 0 , 0 , 0
$QCPDPIMSCFGE: 2 , 0 , 0 , 0
$QCPDPIMSCFGE: 3 , 0 , 0 , 0
OK

I manually inserted the APN value.
+CGDCONT: 1,“IPV4V6”,“internet.lguplus.co.kr”,“0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0”,0,0,0,0
+CGDCONT: 2,“IP”,“internet.lguplus.co.kr”,“0.0.0.0”,0,0,0,0
+CGDCONT: 3,“IPV4V6”,“ims”,“0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0”,0,0,0,0

There are two anomalies in your results.

Your APN for IMS is in context 3, and only context 1 is active.

Please try enabling IMS on context 3 with:

AT$QCPDPIMSCFGE=3,1

Also change the type-of-service for SMS from circuit-switched-only to packet-domain-preferred with:

AT+CGSMS=2

AT$QCPDPIMSCFGE=3,1
OK


AT+CGSMS=2
OK


AT+CGSMS?
+CGSMS: 2
OK


AT$QCPDPIMSCFGE?
$QCPDPIMSCFGE: 1 , 0 , 0 , 0
$QCPDPIMSCFGE: 2 , 0 , 0 , 0
$QCPDPIMSCFGE: 3 , 1 , 0 , 0


AT+CGPADDR
+CGPADDR: 1,“10.85.16.163”
+CGPADDR: 2,“0.0.0.0”
+CGPADDR: 3,“0.0.0.0,0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0”


AT+CGDCONT?
+CGDCONT: 1,“IPV4V6”,“internet.lguplus.co.kr”,“0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0”,0,0,0,0
+CGDCONT: 2,“IP”,“internet.lguplus.co.kr”,“0.0.0.0”,0,0,0,0
+CGDCONT: 3,“IPV4V6”,“ims”,“0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0”,0,0,0,0


What should i do next :T…T

Power-cycle the modem.

If you’re still having problems, you may need to test the SIM in another device.