What you really need to do is to spend time studying the 8051 architecture so that you understand how to do this for yourself - rather than just ask others to do it for you.

The 8051/2 is a very long-established and widely-use architecture - so there is a vast amount of material available in books, application notes, examples, websites, etc.

Essential Reading:

* The so-called "bible" for the 8051: http://www.8052.com/faqs/120112

* Tutorials: http://www.8052.com/tutorial


There are many books avaiable on the 8051; eg, here's a list: http://www.keil.com/books (they are not all specific to Keil).

One word of warning: because the 8051/2 is so long established, there are some materials (especially books) that are now well out-of-date.
Of course, the underlying 8051/2 Architecture hasn't changed; but Implementation details are likely to be well out-of-date - particularly things like ISP, performance, on-chip resources and any references to specific products and/or suppliers.

See: http://www.8052.com/forum/read/175610