Raspberry Pi Forums

Hi,

I've used numerous Huawei USB modems with the Pi 1,2 and 3. I have a dedicated script that checks the lsusb output and on finding a modem that matches the usbmodeswitch data file does the switch and connect with sakis3g. This creates a ppp interface to the internet.

I recently bought a ZTE MF710M USB modem and was surprised that with zero commands it set itself up as a "usb0" interface with IP and is fully connected.

What is this magic? Is this something new? Why do all USB modems not work like this?

So I`ll answer my own question in the off chance someone else stumbles across this.

The ZTE MF710M is unique in that it does not set itself up as a serial port for serial communications. Many other USB dongles present as /dev/ttyUSB0 or /dev/ttyACM0 however the ZTE MF710M is actually based on a USB to Ethernet stack. So when you plug it in the computer thinks it is an Ethernet adapter. The Dongle handles all the 3G connectivity things internally. The drawback of this is that no serial AT commands are possible with this modem and as such tools like gammu wont work for sending and receiving sms/ussd etc.

The modem sets up a basic webs-erver on ip.ip.ip.1 of its range and allows for dongle management.

Although this Ethernet based implementation does simply things, Im not too happy as it causes an additional interface/api to be learned and implemented (I have no clue where to start). i.e. it does not conform with all other modems and AT command suport.

Great explanation!

Three questions,

1- Where can I find ZTE MF710M in the US?

2- Does it work with T-Mobile?

3- Any other 3G/4G USB modems that have the similar operation process that I can use for my RPI?