please help me for writing program for usb in At89c5131 best regards javad majd majd_javad@yahoo.com
No, you really didn't. Exactly how would your situation change if you knew if this forum have other people who have worked with a specific feature for a specific chip? You would still have to make some own work before you would be ready to ask specific questions about specific issues you have - unless your goal is to find someone to send you turn-key code.
What work have you done looking into the USB functionality? Have you looked for existing application notes?
How much time did you spend reading the information available from Atmel? www.atmel.com/.../product_card.asp
What was your conclusions after reading that information? What did you find? What didn't you find? What did you understand? What didn't you understand? What did you start with? How long did you come? Where are you stuck? What are you doing to get unstuck?
your link address gave me more information and now i understand how to write program for using usb in at89c5131 thanks alot for your helping best regards javad majd
So you are saying that you decided to use the processor but never visited the product page? Wouldn't access to datasheet and application notes be a required minimum requirement before being able to go further with a chip selection?
By the way: Atmel has the note "Not recommended for new design: replaced by AT89C5131A-L (full compatibility) or AT89C5131A-M (extended 2.7-5.5V range)."
Or are there more manufacturers making 89C5131 chips?
See: http://www.keil.com/condb