Writing to flash problems

Writing to flash problems

[Chris AtLee]

[-- Attachment #1: Type: text/plain, Size: 1121 bytes --]

Hello again,

After figuring out how to unlock my flash partition, I've been
experimenting with writing to it.  Erasing the partition seems to work
perfectly.

I have a file which contains 2 characters:
12

First I erase the partition with eraseall /dev/mtd3

Then I write data to the partition with
mtd_debug write /dev/mtd3 0 2 data

I retrieve the data with
mtd_debug read /dev/mtd3 0 2 data.new

The contents of data.new is 2 characters:
11

Now, if I repeat the process (without erasing) with the data 22, the new
contents of data.new is 00.

So to me it looks like I have two problems: writing to the words
themselves is not functioning, and the only way to set bits to 1 is by
erasing ('0' == '1' & '2').  In fact, this is in the documentation for
the flash: "If users attempt to program "1"s, the memory cell contents
do not change and no error occurs."

So it looks like I need to erase before writing to fix my second
problem.  I've tried putting in an erase command in do_write_oneword,
but I get timeout errors.

I'd really appreciate any pointers!

Thanks,
Chris





[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 232 bytes --]