marvelous
02-22-2006, 10:50 AM
Hello there,
I want to program a NAND Flash Memory hoping to make an amateurish Flash Disk. I have Low Level I/O Drivers (LLD) for Read, Program and Delete (Erase). I have ECC and Bad Block (Sector) Management. I need Wear Leveling.
Okay..I first want to share with you what I know about those concepts.
1) To start with LLD, I know it is required to read or program a page and to delete a block.
2) ECC is required to manage errorneous pages and this ECC just blocks those pages so that next time no data is lost or corrupted.
3) Bad Block Management is run after writing to a block and it cancels the block if the write was errorneous.
4) Wear leveling is to reduce uneven leveling of blocks.
As for wear leveling, I am planning to count the number of "erase" of each block and then I can write new data (input) to blocks which are less erased or less used. How does that sound to you? Does it sound like a good methodology to prevent wearing?
Okay..do you think I need to have other codes for my flash disk? (other than LLD, ECC, Bad Block Management and Wear Leveling).
By the way, I come up with Flash File System (FFS) when I do a search on the net. What is it really? Do I need to implement an FFS to my device? I am just going to use a simple controller MCU which is to communicate with NAND Flash from parallel port. It will also communicate with the USB host. I will use MSD specifications and I think it leads me to FAT. Can you make a comparison between FFS and FAT if they are comparable?
Do I need to implement some other specific codes to my device so as to make it run in MacOS, Linux and Windows flawlessly?
How can I make my device bootable? (Is it something related to bootloader??).
Okay..see I have lots of question. I am sorry :) Just a beginner.
Any help or idea would be greatly appreciated.
All the best to you!
Marv.
I want to program a NAND Flash Memory hoping to make an amateurish Flash Disk. I have Low Level I/O Drivers (LLD) for Read, Program and Delete (Erase). I have ECC and Bad Block (Sector) Management. I need Wear Leveling.
Okay..I first want to share with you what I know about those concepts.
1) To start with LLD, I know it is required to read or program a page and to delete a block.
2) ECC is required to manage errorneous pages and this ECC just blocks those pages so that next time no data is lost or corrupted.
3) Bad Block Management is run after writing to a block and it cancels the block if the write was errorneous.
4) Wear leveling is to reduce uneven leveling of blocks.
As for wear leveling, I am planning to count the number of "erase" of each block and then I can write new data (input) to blocks which are less erased or less used. How does that sound to you? Does it sound like a good methodology to prevent wearing?
Okay..do you think I need to have other codes for my flash disk? (other than LLD, ECC, Bad Block Management and Wear Leveling).
By the way, I come up with Flash File System (FFS) when I do a search on the net. What is it really? Do I need to implement an FFS to my device? I am just going to use a simple controller MCU which is to communicate with NAND Flash from parallel port. It will also communicate with the USB host. I will use MSD specifications and I think it leads me to FAT. Can you make a comparison between FFS and FAT if they are comparable?
Do I need to implement some other specific codes to my device so as to make it run in MacOS, Linux and Windows flawlessly?
How can I make my device bootable? (Is it something related to bootloader??).
Okay..see I have lots of question. I am sorry :) Just a beginner.
Any help or idea would be greatly appreciated.
All the best to you!
Marv.