Samsung S3C2451X User Manual page 149

S3C2451X RISC MICROPROCESSOR
7
NAND FLASH CONTROLLER
7.1 OVERVIEW
S3C2451X boot code can be executed on an external NAND flash memory. The S3C2451X is equipped with an
internal SRAM buffer called 'Steppingstone'. This supports NAND flash boot loader. When you use IROM boot
and select nand flash as boot device, first 8 KB of the NAND flash memory will be loaded in the Steppingstone by
IROM and the boot code will be executed in the steppingstone.
Generally, In IROM boot, the boot code will copy NAND flash content to SDRAM. At that time IROM uses 8Bit
ECC and the NAND flash data will be checked valid or not. After the NAND flash content is copied to SDRAM,
main program will be executed on SDRAM.
To use NAND Flash Device, The OM and the GPC5/6/7 configuration should be set to use IROM boot and select
proper nand device type. Nand Boot written below is boot device in IROM boot. Refer to IROM application Note
for more information. S3C2451 supports nand boot by using IROM boot mode.
7.2 FEATURES
NAND flash controller features include:
1. Auto boot by: The boot code is transferred into 8-KB Steppingstone after reset. After the boot code is
transfered, boot code will be executed on the Steppingstone.
Note: IROM boot support 8Bit ECC correction on Nand device booting
2. NAND Flash memory I/F: Support 512Bytes, 2KB and 4KB Page.
3. Software mode: User can directly access NAND flash memory. for example this feature can be used in
read/erase/program NAND flash memory.
4. Interface: 8-bit NAND flash memory interface bus.
5. Hardware ECC generation, detection and indication (Software correction).
6. Support both SLC and MLC NAND flash memory : 1-bit ECC, 4-bit and 8-bit ECC for NAND flash.
7. SFR I/F: Support Byte/half word/word access to Data and ECC Data register, and Word access to other
registers
8. SteppingStone I/F: Support Byte/half word/word access.
9. The Steppingstone 64-KB internal SRAM buffer can be used for another purpose after NAND flash booting.
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
NAND FLASH CONTROLLER
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