2 Replies Latest reply on Sep 18, 2020 2:22 AM by alpe_4779926

    S25FL127 page write procedure


      Hello all,

           I am planning to use a S25FL127 nor flash device. I would like to understand if the page program command requires a previous sector erase. For example consider this sequence: I started erasing a 4KB sector, then I write its first page. Some time after that I need to program the second page of the same sector, do I have to erase the whole sector for that (if not, do the previous stored page is modified)?


      Thanks in advance for the help!

        • 1. Re: S25FL127 page write procedure



          No, it is not required to perform sector erase if you are programming page 1 first and page 2 after some time. Sector erase is required only when you re-program an already programmed page.


          In flash memory devices, program operation can change a bit from 1 to 0. It cannot change a bit from 0 to 1. Only an erase operation can change the bits from 0 to 1. So, as long as you are programming erased memory locations inside a sector, it is not required to perform sector erase. If you want to change data already programmed into the flash, then you have to perform sector erase. Please note, a sector erase operation will erase all pages inside a particular sector. If you need to change data only in one page, you have to back up data from other pages before performing sector erase operation. After sector erase operation is finished, program data back to flash.


          I hope the above information answers your query. Please feel free to ask if you need any clarifications.


          Thanks and Regards,