https://devzone.nordicsemi.com/f/nordic-q-a/19930/pstorage-data-did-not-erase-by-bootloaderHI，I want to store some data in 51822. These data was store by my program. I know the pstorage.c could store data. When I do DUF the data could be erased by the bootloader？en-USTelligent Community 13Fri, 24 Feb 2017 08:44:16 GMThttps://devzone.nordicsemi.com/thread/77560?ContentTypeID=1Fri, 24 Feb 2017 08:44:16 GMT137ad170-7792-4731-bb38-c0d22fbe4515:e9d0b8b4-7091-445e-b701-84d5aa574f84bjorn-spockeli<p>Hi Mark,</p> <p>you are correct in that data stored using pstorage will be erased during a DFU if the bootloader is not configured to preserve application data during a DFU. This is done by setting the</p> <pre><code>#define DFU_APP_DATA_RESERVED 0x0000 </code></pre> <p>in dfu_types.h to the number of bytes, note it must be a multiple of the flash page size, you want to preserve. This is described in detail <a href="http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk51.v9.0.0/bledfu_memory_appdata.html?resultof=%22%70%72%65%73%65%72%76%65%22%20%22%70%72%65%73%65%72%76%22%20%22%61%70%70%6c%69%63%61%74%69%6f%6e%22%20%22%61%70%70%6c%69%63%22%20%22%64%61%74%61%22%20">here</a>. The value of DFU_APP_DATA_RESERVED corresponds to the number of bytes below the bootloader start address, which is where pstorage stores data, that will be preserved during a DFU, you can see the memory layout on <a href="http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk51.v9.0.0/bledfu_memory.html">this</a> Infocenter page.</p> <p>Best regards</p> <p>Bjørn</p><div style="clear:both;"></div>