Are you asking someone to write your code for you, and then debug it on your system for you?
Or are you looking for examples of file I/O code, to use as a guide for writing your own code?
Have you used the search engine for this website to dig up the answers to your own question? File I/O and UARTs are probably some of the top 100 subjects for these forums. You should be able to find all the information you want, and much more.
-- Bob Elkind
SIGNATURE: README for newbies is here: http://forums.xilinx.com/t5/New-Users-Forum/README-first-Help-for-new-users/td-p/219369
Summary: 1. Read the manual or user guide. Have you read the manual? Can you find the manual? 2. Search the forums (and search the web) for similar topics. 3. Do not post the same question on multiple forums. 4. Do not post a new topic or question on someone else's thread, start a new thread! 5. Students: Copying code is not the same as learning to design. 6 "It does not work" is not a question which can be answered. Provide useful details (with webpage, datasheet links, please). 7. You are not charged extra fees for comments in your code. 8. I am not paid for forum posts. If I write a good post, then I have been good for nothing.