[U-Boot-Users] make env
Wolfgang Denk
wd at denx.de
Wed Apr 2 12:39:50 CEST 2008
Dear Manuel,
in message <47F3528A.3000202 at feig.de> you wrote:
>
> My problem the structure of the enviroment:
> If I understand:
> 4 byte crc; 1 byte flags, 0x20000-5 byte data.
Correct - the flag byte is only present if you use redundant
environment.
> The CRC is over the data bytes,( not the flags byte included) , right ??
Correct. That's because the flasg byte indicates the state of the
environment copy (current -> bit = 1, or obsolete -> bit = 0). It
relies on the feature of NOR flash that you can always program '1'
bits to '0', even single bits in a single byte.
> What about the flag byte, which values should I have to write here ?
See above. But you might have problems doing such a thing on NAND
storage.
Best regards,
Wolfgang Denk
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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