how can i access memory contents using ubuntu 11.04

Linux is a layered system which means that direct control or interrogation is not a simple matter. See this kernel map from wikipedia:
http://en.wikipedia.org/wiki/File:Linux_kernel_map.png

You can get information on memory usage and running processes by by typing the following in terminal:

top

Press 'Q' to exit top. You can get information on the hardware include the processors by typing the following in terminal:

sudo lshw

It sounds like you might have Ubuntu installed using Wubi rather that dual boot. With Wubi install you install Ubuntu into Windows and remove it with the Windows add/remove programs. With a true dual boot system the OS has it's own partition to boot off.

Chrsi

Hi Chris,
             Thanks for your information and i know the top and lshw commands, but i want in depth knowledge of ubuntu to know more about hardware and pheripherals information. But i don't know how to ask this question beyond your reply.
             I am not using wubi and i am totally using ubuntu on separate hard disc partition. Even i don't know the function of wubi and i heard about it.

Hi, try the pmap command for more information on what memory is allocated, however it's still not going to give you physical memory addresses - only the memory used by modules that are used by a process and private memory, and the offsets.

The layered architecture of the Linux kernel insulates the programmer and therefore the user from the actual physical memory management so it's not very easy to pin the memory used by a module to a particular physical memory address. For more information on this Gorman's book on Linux virtual memory management gives a very good insight: http://www.kernel.org/doc/gorman/pdf

Similarly, the layered approach provides a standardized interface for all other peripherals in the system, a HAL (Hardware Abstraction Layer), so that rather than dealing directly with the hardware a programmer needs to only deal with this HAL If a programmer wants to write a driver module for the Linux kernel, he must write it for use within this abstraction layer so that program modules can use it.

There are some very good reasons for the way this done:

Portability: To a large extent if you want to port the OS to a different platform, only the hardware layer needs to be re-written. It's not quite as simple as this of course, but there would be no need to re-write the entire OS.

Security: Since a module cannot access physical RAM directly there's almost no chance that a badly written (or malicious) application can affect another module or it's data, including the kernel.

Optimisation: individual modules can be optimised for a particular hardware or situation. There are some performance trade-offs with the layered approach of course, however given that computers have evolved beyond the single user, single task, and even single CPU paradigm it's still the best approach for a mature OS.

So, what you're asking for isn't really possible within the scope of what a normal user or even a programmer is expected or allowed to do.

Chris