Title: +038=360.000-OU045T_02-PCD2.m4160 PLS SBC - File system Manual.pdf
Flash devices dedicated to file system are organized into pages (256 / 512 bytes 1), blocks (512 Bytes … 8 KBytes 1) and sectors (64 KB). A page is a unit of write, a block is a unit of file and a sector is a unit of erase. This means that the smallest part of the flash memory that can be written is a page of 256 bytes while the smallest area of a flash device that can be erased at once is 64 KBytes.If a file is created, at least one block (e.g. 2 KBytes) is allocated to that file. Even if the file is smaller than this, the place taken on the device in this case is 2 KB. When the 2 KB are filled with file data, a new block will be taken and the size taken on the device will be 4 KB.On each module dedicated to flash file system some space is reserved for file system internal data (one block of 64 Kbytes is reserved and some blocks are used for file system internal data). This means that a bit less than the specified flash size can be used by the user.2.2.2Deletinganderasingdataonflashdevices