Have you ever wondered what is happening when you phone starts, how the phone interacts with your SIM card? Well, now you can easily see the messages that are exchanged between your phone and the SIM by using Android emulator.
First of all, download the Android SDK for Linux. Extract the archive then go to the “tools” directory on the newly extracted directory. Launch the SDK Manager by entering “./android”. Here you’ll have to choose Available packages and from the right panel open Android repository. Select the SDK platform that you want and Install it. Now we should create two virtual phones based on this SDK. Go to Virtual Devices, choose New. On the new window set a Name for your device, a Target (the SDK package installed previously) and a size for your virtual SD card. Repeat the steps to create a second device.
Have a look:
Why two phones? Because we need to place some calls in order to better understand AT messages exchanged between phone and SIM.
Now you should start the first phone and then open another terminal window. You’ll have to go where Android SDK was extracted, “platform-tools” folder and type “./ adb shell”. This way you’ll enter into debug mode. In order to see the AT messages type “logcat -b radio”. You can now open the second phone. In order to place calls between the phones, each one has a unique number – found in the title bar of the phone window.
To better visualize these things, a video is necessary:
Of course you can try the AT commands that you see by connecting a USB GSM modem and minicom (or HyperTerminal in Windows). Enjoy!