Both Linux and Mac can be connected directly, but Windows must be driven below.
The driver of the official web is no use. It works https://drive.google.com/uc?id=0Bw8B2a85Qa1jSldjc3RIM3pkNWc.
Then in Device Manager, Update Driver Software, Browse for the Driver software on your computer-let me pick from a l Ist from ....
Select the INF file in the download folder, choose android Device, and select Asustek Computer INC can then be seen at manufacturer. Model selection asus Android ADB Interface
Then check the Allow USB debug in Developer option in the tablet, and cancel all the options in the top right corner of storage!!!
This way the tablet will be prompted to connect to the computer, and you can see the device in ADB devices
Http://singledrivers.blogspot.com/2014/01/asus-google-nexus-7-2013-usb-driver-for.html
Windows connect under debug ASUS Nexus 7 Tablet