FAQ's on Ethernet,UART,USB

I need some FAQ's on Ethernet,UART,USB according to VHDL programming..
Can anyone please let me know if anyone have them..
Thank you

Hi

What is that you are exactly looking at? For design part, u can always refer IEEE specs for Ethernet. For USB you can refer USB forum specs. If you have any specific question about ethernet or USB, let me know.

DTN

I am sorry for not being clear.I want the FAQ's interview point of view.
Like which type of questions are asked in the interview on these topics...

You need to know the protocol well for any interviews. It can be ethernet or usb, they deal with data transfer. For both the designs, one side there will be a standard bus interface(AHB/PCI/OCP ...etc). On the other side, both will have PHY layer .
In ethernet the main part is transmission & reception of data to & from mac layer. Complete data flow should be understood. Few questions in ethernet include
1. Full/Half duplex difference
2. Ethernet in OSI model
3. Clock frequencies at which ur ethernet is working(10MBPS/FAST/Gigabit)
4. Auto Negotiation concept on phy side etc....

From USB point of view, again the protocol plays the important part:
1. How data is flowing from one end to other end( bus interface to phy & viceversa)
2. Bit stuffing, NRZI etc.
3. Latest evolutions in USB(like OTG)
4. What host is doing & what device is doing etc.
5. Serial Interface Engine part of your USB design

Hope I answered your query in a right way.

DTN

Thank you so much for your reply.
I am not finding a nice document on ethernet where in i can study and start writing the code..If you have any can u please provide it..

thank you

U can download a free copy from IEEE site. Ethernet specs are freely available on net.