EC25 custom SW interface

Technical Subjects Software General Function
1

Dear Forum.
We have a simple Software interface on Window and Linux PC, that connect to a old module via serial port (the module use UART, the a UART to USB bridge show us a COM on window); so, via AT command, we send SMS, receive SMS ,connect to GPRS ecc…Enough simple .
Now, we wand to move to the EC25 or EG25,but not using only UART, but using USB also for data speed .
This start my confusion : I install a Window driver ,and connect my EC25 to the USB of PC.
Question are:

  1. Where on window (same will be for linux )I can see my AT interface ,and where my USB for send data?
  2. If i use AT command, why I see example with PPP or QMI or ECM …Why I need this protocol if AT commands can -command- the module to SMS, TCP IP ecc…

Thanks very much,and excuse for long mail.
Roberto

2

For the first question, I think if the installation of the driver is OK, it can be seen in the device manager of my computer. If you need the driver, please send me the email. I’m sorry, I don’t quite understand the second question.