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RL-ARM User's Guide
RL-RTX 
RL-FlashFS Flash Memory Management 
Memory Organization File Allocation Information File Data Blocks Technical Data Configuring Flash File System Configuration Flash Device Sector Memory Map FS_FlashDev.h Converting FlashDev.c Program and Erase Code FS_FlashPrg.c Converting FlashPrg.c SPI Flash Device FS_SPI_FlashDev.h Programming Code FS_SPI_FlashPrg.c RAM Device Memory Card Device MCI Interface SPI Interface File Time Support System Configuration Library Files Using Flash File System Using Flash Devices Using Dedicated Flash Devices Using One Large Flash Device Using Internal Flash Devices Using RAM Devices RAM Configuration Example Using Memory Card Devices Hot Insertion Root Directory Limitation Debugging Function Overview File I/O Routines File Maintenance Routines File Time Support Routines Low-Level Routines SPI Interface Routines System Functions RL-TCPnet RL-CAN Example Programs Library Reference AppendixFS_FlashDev.h
The memory map is specified in the FS_FlashDev.h description header file. Every device has it's own description file. Those files are located in the \Keil\ARM\RL\FlashFS\Flash folder.
To generate a FS_FlashDev.h description file, copy the flash sector layout information from the Flash Device datasheet.
You need to specify a sector size in bytes and a sector base address relative to a Flash Device Start address. Macro DSB converts this information into the RL-FlashFS compatible sector description.
The following example shows a Flash Sector layout configuration description for the 25F160S33 Intel SPI Flash Device:
#define SPI_FLASH_DEVICE \ DSB(0x10000, 0x000000), /* Sector Size 64kB */ \ DSB(0x10000, 0x010000), /* Sector Size 64kB */ \ DSB(0x10000, 0x020000), /* Sector Size 64kB */ \ DSB(0x10000, 0x030000), /* Sector Size 64kB */ \ DSB(0x10000, 0x040000), /* Sector Size 64kB */ \ DSB(0x10000, 0x050000), /* Sector Size 64kB */ \ DSB(0x10000, 0x060000), /* Sector Size 64kB */ \ DSB(0x10000, 0x070000), /* Sector Size 64kB */ \ DSB(0x10000, 0x080000), /* Sector Size 64kB */ \ DSB(0x10000, 0x090000), /* Sector Size 64kB */ \ DSB(0x10000, 0x0A0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x0B0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x0C0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x0D0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x0E0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x0F0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x100000), /* Sector Size 64kB */ \ DSB(0x10000, 0x110000), /* Sector Size 64kB */ \ DSB(0x10000, 0x120000), /* Sector Size 64kB */ \ DSB(0x10000, 0x130000), /* Sector Size 64kB */ \ DSB(0x10000, 0x140000), /* Sector Size 64kB */ \ DSB(0x10000, 0x150000), /* Sector Size 64kB */ \ DSB(0x10000, 0x160000), /* Sector Size 64kB */ \ DSB(0x10000, 0x170000), /* Sector Size 64kB */ \ DSB(0x10000, 0x180000), /* Sector Size 64kB */ \ DSB(0x10000, 0x190000), /* Sector Size 64kB */ \ DSB(0x10000, 0x1A0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x1B0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x1C0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x1D0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x1E0000), /* Sector Size 64kB */ \ DSB(0x10000, 0x1F0000), /* Sector Size 64kB */ \ #define SF_NSECT 32
To improve the RL-FlashFS performance, the sector information is stored as a table in the code. The RL-FlashFS scans this table when accessing files from the SPI Flash Device.
Flash File System writes allocation information at the top of each sector. It is not optimal to use Flash Devices with a lot of small sectors. In this case more optimal solution for the FlashFS would be to join several physical sectors into bigger virtual sectors. In this case a fs_EraseSector() function shall be modified to erase a virtual sector, not a physical sector.
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