Configuring a ZTE AD3700 CDMA Modem for Intertelecom on Linux

Consider the setting of such a modem here. According to the passport, he is called ZTE AD3700.

The Intertelecom provider at one time apparently purchased a whole KAMAZ of such decommissioned modems. Similar CDMA modems are used by other providers, such as PeopleNet. Yes, actually for many devices based on the Qualcomm gobi chipset, this guide should work.

We will need this one archive here:

• mirror 1

It contains the firmware for the modem, two versions. So which firmware version is suitable depends on the modem revision. But we will come back to this later.

Supplement from user palexxx from 03.10.19 :

The fact is that the modem is two-standard. But due to the economy, the vendor saved on memory and each time it is defined in the modem as a DL port and the firmware is poured. Depending on which firmware is different functionality. You have two options in the article, but this is not for "different revisions of the device." And one of you is CDMA version, and the second is strange, but not GSM. Both options are checked personally - it calls both CDMA Intertelecom and HSDPA with SIM of any operator. In the wvdial config, you only need to change the dialing number. Links to two firmware options for the ZTE AD3700 drive.google.com/file/d/1-fMmKFJZjMmWoivPfqi3ph7PTg1pIe3S/view?usp=sharing

First you need to install wvdial:

apt-get install wvdial 

Now in the editor from under the root, open the file "/etc/wvdial.conf", its contents for Intertelecom:

 [Dialer Defaults] Init1 = ATZ Modem Type = USB Modem ISDN = 0 New PPPD = yes Stupid Mode = 1 Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0 Modem Type = Analog Modem Modem = /dev/ttyUSB0 Baud = 460800 Phone = #777 Username = IT Password = IT 

Instead of / dev / ttyUSB0, write the name of the device that the kernel issued to the modem. Login and password "IT" are the same for all users. Phone too. If you have another provider, then change the settings to your own. Next, we need to add udev rules so that when the modem is turned on, the correct firmware is loaded. To do this, you need to go to the “udev” folder from the archive above and from there enter the command:

 make install 

Now, if everything worked out without errors, create a directory named "/ lib / firmware / gobi". There are two directories in the archive - “variant1” and “variant2”: these are different firmware versions for different modems. To find out which one fits your modem:

1. Copy all files from the "variant1" directory to the "/ lib / firmware / gobi" directory.
2. Plug the modem into the USB port. If it is already inserted, pull it out and insert it again.
3. Wait about 10 seconds for him to respond to commands.
4. Make sure that the modem has determined the device name that you specified in "/etc/wvdial.conf", if not, then fix the config.
5. Run from under the root "wvdial".

If the firmware is selected incorrectly, then after a short wait, wvdial will crash with the message “Modem is not responding”. In this case, repeat all 5 points again, just copy the files from the "variant2" directory into "/ lib / firmware / gobi".

In the case of a working firmware, “wvdial” will spit out the addresses of the received DNS servers into the console, and the word pppd will also be there. In theory, you now have internet.

I did not manage to force network-manager to work correctly with this connection. Also, if you interrupt the connection via “Ctrl-C”, then it will not be possible to reconnect without transferring the modem to the USB port. It also means that after each rewrite, you will most likely have to edit the "/etc/wvdial.conf" file to make sure that the correct modem file is specified instead of / dev / ttyUSB0.

Sometimes it happens that “wvdial” starts writing nonsense to the console at different intervals of time - this means that the modem is frozen, you need to rewind. Do not forget to wait 10-15 seconds each time after sticking, otherwise the connection will not work. If you shake something, the modem can get very hot, but it does not affect performance.