[PIC] Pic18f4550 and usb cdc

[nick703]

hello friends ,

i have to implement pic18f4550 to usb cdc basic demo . if any one have complete communication PC to pic and pic to PC using Proteus then step by step information give me. i am confused about endpoint and usb traffic .
and also is that any problem if our micro 18f4550 is powered up using usb port of computer ?
and usb communication is half-duplex mode right then suppose windows form based application using c#.net send command like {HELLO} then micro controller respond this string to [HELLO] format using
usb cdc class.

 

[nick703]

and also c# .net application is based on this articles .
https://www.codeproject.com/Articles/60579/A-USB-Library-to-Detect-USB-Devices?msg=4676391#xx4676391xx.

 

[nick703]

and also why the datasheet AN1164 based this statement say

Note: Once any quantity of data is reported by
the USBUSARTRxGetLength routine, the
CDC serial driver will not accept additional
data from the host until the USBUSARTRx
routine is called again.
Since this simple application is only
designed to be “half duplex”, either transmitting
or receiving (but, not both at the
same time), it will not call USBUSARTRx
again immediately. A more advanced
application could do so using a different
buffer, allowing the system to appear to
receive data at the same time it was transmitting
data, providing “[B]full-duplex”[/B]
functionality

so is that possible to do full duplex in USB cdc mode ?????because USB is half duplex mode . so i am confused and what's the deal of that type to achieve full duplex functionality USB device.