https://devzone.nordicsemi.com/f/nordic-q-a/16328/nrf51-pstrorage-write-zeros-to-flash-memoryI&#39;m trying to write some data to flash memory (32 bytes) every 1 minute. the data are not NULL but then I noticed that sometimes (not always) the pstroage module write zeros to flash memory. I can check that it&#39;s NULL data which are written by dumptingen-USTelligent Community 13Mon, 12 Sep 2016 05:11:35 GMThttps://devzone.nordicsemi.com/thread/62403?ContentTypeID=1Mon, 12 Sep 2016 05:11:35 GMT137ad170-7792-4731-bb38-c0d22fbe4515:33a6475d-8904-419e-8b8f-7da8f3805b51Stefan Birnir Sverrisson<p>Hi</p> <p>You can only write once to a certain flash memory area. If you want to write to it again you must erase it first. Erase is performed on a whole page.</p> <p>The pstorage module queues the flash operations, e.g. pstorage_store and pstorage_clear, so you dont really need to wait for the pstorage_clear to finish before calling pstorage_store, pstorage module will take care of that. You do however need to wait for pstorage_store and pstorage_clear before reading the flash memory (with e.g. pstorage_load) because reads are read directly from flash and are not in queue in pstorage module. Otherwise you will read the flash contents before it is written/erased.</p> <p>There is pstorage example available <a href="https://devzone.nordicsemi.com/question/15271/how-can-i-write-10kb-of-data-to-internal-flash/?answer=17300#post-id-17300">here</a>.</p><div style="clear:both;"></div>