I have a modem Huawei E1752Cu HSPA, and I want it to connect to the internet.

After connecting the modem, perform a lookup of the syslog. It will show you the vendor and the product:

Feb 28 21:18:39 raspi kernel: [ 1432.602724] usb 1-1.2: new full-speed USB device number 12 using dwc_otg
Feb 28 21:18:39 raspi kernel: [ 1432.737215] usb 1-1.2: New USB device found, idVendor=12d1, idProduct=1004
Feb 28 21:18:39 raspi kernel: [ 1432.737239] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Feb 28 21:18:39 raspi kernel: [ 1432.737250] usb 1-1.2: Product: HUAWEI Mobile
Feb 28 21:18:39 raspi kernel: [ 1432.737259] usb 1-1.2: Manufacturer: HUAWEI Technologies

So, in my case the vendor id is 12d1 and the product is 1004.

# apt-get install usb-modeswitch

Then open the modem definition file, which in my case is /usb/share/usb_modeswitch/configPack.tar.gz and then copy one existing similar to ours. In my case, I've found the 12d1:1003, so I've copied it to create my own configuration of modeswitch:

cp 12d1:1003 /etc/usb-modeswitch.d/12d1:1004

So, after that we will see that the modem is recognized.

The configuration for me resulted as:

[Dialer Defaults]
Modem Type = USB Modem
Phone = *99#
ISDN = 0
Username = "pepephone"
Password = "pepephone"
Stupid Mode = 1
New PPPD = yes
Modem = /dev/ttyUSB0
Baud = 460800
Init1 = ATZ
Init2 = AT+CPIN="YOUR-PIN-CODE-HERE"
Init3 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
Init4 = AT+CGDCONT=1,"IP","gprs.pepephone.com"
Auto DNS = 1
Dial Command = ATDT
Carrier Check = yes
Stupid Mode = 1

This was the most difficult part, because It requested me to guess what the configuration optimum for the modem.

In “Modem”, you have to select the device of the modem, after it is connected.

The date “Phone”, “Username”, “Password”, and Init*. The Init* sequence cost me because you have to guess the at commands that suits your modem.

There are many ways to send an sms. You can send it directly, write first the message into the memory of the modem, etc…

Direct sending

AT+CMGF=1               # say the modem to operate in sms mode
OK
AT+CMGS="669807321"     # send a message directly
> text your message here, and end the message with ^Z (control+z)

AT+CMGF=1               # say the modem to operate in sms mode
AT+CMGW="669807321"
> A simple demo of SMS text messaging.

+CMSS: 1                # the ID of the message in memory

AT+CMSS=1               # send the message with id = 1 

To list all the messages in the memory:

To delete a message:

AT+CMGD=2