Why such an old ISE version?
What is your clock speed?
How can your data width "vary later"?
1000 what? bits or words? 20 bits per word?
What are the interfaces you're using?
You still have not answered these questions from earlier - without more details we cannot do anything more than guess.
actually now since interfacing is not possible , so i am designing an LFSR(linear feedback shift register) of 20 bits which is providing random numbers which am considering as input data . Am storing those data in a memory and after every 100 ns , i am transfering this data from this memory to another as if this memory now is acting as a data source .This much i have done. but i am having problem with data transfer , because simple parallel transfer of so many 20 bits data from 1 memory to another is not possible.
i dont have any diagrams now , i will try to update soon . Here the LFSR is running at a clock time period of 2 ns.