I am using char Array. For first time i store data in array. Before Next data Storing i will have to empty the array. i dont know how. thanks
Use memset() or zero each array element.
Depending on your application, It may be sufficient just to set the 1st element to zero. (eg, as far as 'C' string functions are concerned, that would be considered an "empty" string)
Why do you need to empty the array? You can implement some type of simple head/tail pointer system and always write a NULL for the last entry. You can then test for last entry or you can initialize the pointer back to the initial entry and overwrite with new data instead of clearing the array. On this website, there are a number of examples of serial data input using circular buffers.