I have used atmega32u4 which supports native usb, when i connect the usb to pc no pop up notification appears. my understanding is that 32u4 virgin chip has usb dfu flashed.
so when it is connected to pc it should appear as atmega32u4dfu device, but when i connect nothing happens. when i referred usb self powered 3.3v topic the uvcc pin was left floating but in my schematic its tied to vcc. Also tried hbe pin to reset so it executes bootloader but it was of no use.
Is the uvcc pin causing the trouble or some design flaw in my schematic .
Any suggestion would be helpful, thanks in advance.