Dumping ROM using ADB guide
What you need :
a pc, usb cable and your android device with sdcard
What you need to download :
Android SDK. here's the link on how to install it and download link.
. Setting Up an Existing IDE | Android Developers
1. enable USB debugging on the device
2. Download and Install android SDK (dont forget JAVA JDK if you havent got it yet)
3. now connect your device to your pc, you will see Windows will try to install appropriate driver for your device, if it installed properly then you're lucky, you can proceed to step 4, if not then we need to install the driver using USB driver
how to install driver
now for the adb part..
4. copy RKdump file you downloaded on the same folder as ADB.exe, usually its in folder Program Files (x86)/android/android-sdk/platform-tools
5. click menu and on search bar, type cmd, right click cmd.exe and run as administrator.
6. on the cmd command prompt, type "cd\program files (x86)/android/android-sdk/platform-tools" without the quote.
adb push rkdump /data/
*if you see a "#" sign and a cursor next to it then we're good to go.. otherwise..you need to root your phone first
chmod 755 /data/rkdump
*this will make RKDump executable
/data/rkdump /dev/block/mtdblock5 /sdcard/update.img
*this will copy update.img on your sdcard which can be used for faulty same device (in case if you not find any factory flasher or flash file)
note: if you want to copy any other part of your device partition.. look in here rkutils | androtab.info