Binary Nandwrite/read to Flash

Hello,

is it possible to write directly to nandflash, or to store a file in nand flash ?

Thank you,

could you tell me the exact call:

I have a NAND-Flash with PAGESSIZE = 0x800 and ERASEBLOCKSIZE=0x20000

I want to write a file maybe called "test.txt" at adress 0x02000000 of the NAND flash.

And read it back to a file "test2.txt" afterwards.

Quoted 7 lines · Manuel Sahm

Thank you,

could you tell me the exact call:

I have a NAND-Flash with PAGESSIZE = 0x800 and ERASEBLOCKSIZE=0x20000

I want to write a file maybe called "test.txt" at adress 0x02000000 of the NAND flash.

Something like

nandwrite -s 0x02000000 -p /dev/mtd0 test.txt

(mtd0 depending on which device your nandflash is)

(Note: you don't have to specify the padding size, nandwrite figures it out by querying mtd).

Quoted 1 line

And read it back to a file "test2.txt" afterwards.

Something like

nanddump -o -b -s 0x02000000 -l <filesize> -f test2.txt /dev/mtd0

where <filesize> is the size of your file.

/Ricard

Signature · 3 lines

Ricard Wolf Wanderlöf                           ricardw(at)axis.com
Axis Communications AB, Lund, Sweden            www.axis.com
Phone +46 46 272 2016                           Fax +46 46 13 61 30

Thank you very much....

Is it possible to write/read to the NAND flash "directly" without an partition ?(/dev/mtdX) ?

Quoted 3 lines · Manuel Sahm

Thank you very much....

Is it possible to write/read to the NAND flash "directly" without an partition ?(/dev/mtdX) ?

No, but you can set up a /dev/mtdX device to span the whole device, even if you then have additional /dev/mtdX devices which refer to partitions.

/Ricard

Signature · 3 lines

Ricard Wolf Wanderlöf                           ricardw(at)axis.com
Axis Communications AB, Lund, Sweden            www.axis.com
Phone +46 46 272 2016                           Fax +46 46 13 61 30

Quoted 4 lines

Quoted 1 line

Is it possible to write/read to the NAND flash "directly" without an partition ?(/dev/mtdX) ?

No, but you can set up a /dev/mtdX device to span the whole device, even if you then have additional /dev/mtdX devices which refer to partitions.

it´s very dangerous, because if I use the wrong address I´ll kill my system :-)

Is ther a possibility to make the /dev/mtdX read only (write protected) ?

Quoted 3 lines · Manuel Sahm

Hello,

is it possible to write directly to nandflash, or to store a file in nand flash ?

Yes, use the mtdtools applications nandwrite and nanddump in order to skip bad blocks during read and write. You'll need the pad option to nandwrite in order to fill out to an even multiple of the page size.

If you're writing a file, it really is raw byte by byte, with no indication of file size, access times etc, so to the extent you need that info you'll have to store it explicitly.