What is deep flash ?
The fault equipment can enter FASTBoot mode through the volume down key and the power button combinations and the driver can be recognized normally. But for the fault equipment which has damaged deeply in the system and unable to properly identify the port,the deep flash will be needed
Take out the battery of the fault equipment
Connect computers by usb cables
Conduct the deep flash point by metal tools,
Force the underlying driver of the chip to work, so that computer can identify the USB port.