Hi, i am a bit confused with connecting a usb port to atmega8L. Many websites say that usb port can't be used with atmega8L. Is this through? if we can't use usb port, what is the alternative??

 

The atmega8L is a 3.3v device.

USB is 5v.

You would need a separate chip to handle the usb communications or a level shifter IC, then you could bit-bang.

Save yourself a ton of headaches and get a uC with on-board USB.. There are many to choose from.