Hello Ahmed
I can't help with PE - it will presumable have configured an SPI interface, which is however only about 1% of the code needed to actually use SPI Flash.
You will need to see whether PE includes any addition support for the SPI Flash itself and add it if it does. If it doesn't, you will need to study the interface the PE has given you and then either write the rest yourself or search the Internet for examples and port these accordingly.
As starting point I have attached the low level interface used by the uTasker project and the ATMEL SPI Flash on the TWR-K24F120M. In order to actually use the Flash a higher level driver interface is required to coordinate the use of the commands and the mapping of address area. On top of that you may need also a file system unless you are doing simple data writes to fixed addresses.
Regards
Mark
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