Hi sandeep,

On Mon, Jan 9, 2012 at 10:37 PM, sandeep kumar
[off-list ref] wrote:

Hi All,

I want to know "What is a console?

A console is where the output from printk goes.

and Why it is always associated with
UART?"

While console's may often be associated with a UART (typical for
embedded systems) there is no need or requirement for them to be
associated with a console. You can regitser a console to send the
output wherever you like.

What is a serial console??

A serial console is a console driver (registered via register_console)
which sends the output to a serial port, typically also allowing the
serial port to be used as a tty interface.

Can there be a USB console??

Sure. I don't know if a driver for this exists yet, but if it doesn't
you can always write one.

There is already something called a netconsole (see
Documentation/networking/netconsole.txt). This is an example of a
console which isn't associated with a serial port.

There is also a framebuffer console (See Documentation/fb/fbcon.txt)

-- 
Dave Hylands
Shuswap, BC, Canada
http://www.davehylands.com