Babar:
I suggest you select the things you need right now for your learning and / or development activities. This way you can get right on to getting your project completed. You will find this the most profitable path and the one that provides the most satisfaction from learning.

You will probably find out soon enough that there is no such thing as a universal development board. There are a number of things which cause this....

- If you spend a lot of time trying to devise the "universal" board you will end up putting things on there that you will never need or that you will never find the time to write software for.

- There are literally 100's of microcontroller components in the market place. As you go forward a strong capability to develop is the ability to select from these many choices those which best answer the project goals at that time. A generic 'C51RD2 design will not always be the right solution.

- Every project you undertake will have different requirements and so a different design solution will be needed for each. (At least lets hope you do not have to keep doing the same design over and over again for years....I'd quit that path and find something different just to be able to stay fresh and on the learning path).

- Part types, speeds, packages and voltages are changing so fast that it is hard to even anticipate that some parts we see today will be applicable for new designs in as short of times as a couple of years!!!

Michael Karas