EG915U not getting IP address

Technical Subjects Driver
1

Hello,
We are using EG915 and connect it to raspberry over the USB interface
The device occurs on ifconfig, but there is no IP. The device is in default ECM mode.

usb0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
ether 02:4b:b3:b9:eb:e5 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

Right now the sim card is in Roaming mode. I am checking the state with:
sudo minicom -D /dev/ttyUSB0
AT

OK
AT+CFUN?

+CFUN: 1
AT+COPS?

+COPS: 0,0,“vodafone.de”,0

OK
AT+CPIN?

+CPIN: READY

OK
AT+CREG?

+CREG: 2,5,“0134”,“282A”,0

OK
AT+QNWINFO

+QNWINFO: “GPRS”,“26202”,“GSM 900”,3

OK
AT+QCFG=“usbnet”

+QCFG: “usbnet”,1

OK
AT+CGATT?

+CGATT: 1

OK
AT+CGDCONT?

+CGDCONT: 1,“IP”,“internet”,“0.0.0.0”,0,0

OK
AT+CEREG?

+CEREG: 0,0

Can you please help to fix the problem that the device does not get the IP address and there is no communication?

2

You need to send the AT command

AT+QNETDEVCTL=1,1,1

and then run DHCP

busybox udhcpc -i usb0

3

First you need to register on the LTE network and then “dial” as shown above.

4

Thank you. Can you please write how to force to register to LTE network?

5

I would use +cops to list networks and technologies available and disable all fhe RATs except LTE.

6

With AT+COPS=? I am getting this:

AT+COPS=?
+COPS: (1,“o2 - de”,“o2 - de”,“26203”,0),(1,“vodafone.de”,“Vodafone”,“26202”,0),(1,“Telekom.de”,“TDG”,“26201”,0),(0-4))

It seems this is 2G only? I will move around the city. However, shouldn’t IP assignment also work on 2G?

7

Yes, 0 is the Access Technology that is available, 0 is GSM and 7 is E-UTRAN.
Make sure you have the proper antenna attached and check the output of

AT+QCFG="band"
AT+QCFG="nwscanmode"

Please use </> button to format the terminal output.

8

Thank you for your answer. I moved to the city center, however there seems to be less networks. At the moment I only have Molex flexible antenna 824-2170MHz, serial number 207235.

The answers from the “band” and “nwscanmode” are below:

AT+CGATT?

+CGATT: 1

OK
AT+CEREG?

+CEREG: 0,0

OK
AT+QCFG="band"

+QCFG: "band",0xf,0x80800d5
AT+QCFG="nwscanmode"

+QCFG: "nwscanmode",0
AT+COPS=?

+COPS: (2,"vodafone.de","Vodafone","26202",0),,(0-4),(0-2)
9

Based on this I suppose, I have to change it to EU bands:

AT+QCFG="band",3,800015,1
OK
+CREG: 0
+CREG: 2,"0134","282A",0
+CREG: 5,"0134","282A",0
+CGREG: 5,"0134","282A",0

After this I get response, which seems the B20 was not set for some reason

AT+QCFG="band"
+QCFG: "band",0x3,0x15
AT+QNETDEVCTL=1,1,1
OK
+QNETDEVSTATUS: 0
AT+QNETDEVCTL?
+QNETDEVCTL: 0,0,0,0
OK
10

That’s absolutely fine - 0x80800d5 corresponds to LTE bands “B1 B3 B5 B7 B8 B20 B28”, there is no reason to change it.

11

Ok, I changed it back:

AT+QCFG="band",3,80800d5,1
OK
+CGREG: 0
+CREG: 0
+CREG: 2,"0134","282A",0
+CGREG: 2,"0134","282A",0
+CREG: 5,"0134","282A",0
+CGREG: 5,"0134","282A",0
AT+QCFG="band"
+QCFG: "band",0x3,0x80800d5
OK

Would you have any additional suggestion?

12

Any chance to test with the local SIM?
I don’t currently see a reason why it cannot see any LTE network.
See also No ip configuration

13

Thank you. At the moment I cant test with local simcard. I can do with local SIM in another country tomorrow.
I also did some commands from your mentioned link:

AT+QNETDEVCTL?
+QNETDEVCTL: 3,2,0,0

So this one seems states automatic connection to network. And the PDP context is 2. I think it should be 1? However, it seems that I cannot change it.

AT+QNETDEVCTL=3,1,1
+CME ERROR: 53

AT+CGACT=0,2
OK
AT+CGACT=1,1
+CME ERROR: 3
AT+CGDCONT?
+CGDCONT: 1,"IP","internet","0.0.0.0",0,0
+CGDCONT: 2,"IP","","0.0.0.0",0,0

AT+QENG="servingcell"
+QENG: "servingcell","NOCONN","GSM",262,02,134,282A,58,3,2,13,5,97,0,9,9,-,-,-,-,-,-,-,-,-,-,"-"
OK
AT+QNWINFO
+QNWINFO: "GPRS","26202","GSM 900",3