Manuel Sahm <[EMAIL PROTECTED]> writes: > how does uboot handle this flag byte ? (i I use redundant nand)
As you can't invalidate the old NAND environment as you can with NOR flash, counters are used instead. So for NAND, the flag byte is a counter which gets incremented for each write. This means the environment with the flag containing the larger value is the valid one, except for the case when the counter overflows and the valid environment flag holds the value 0 and the former one 255. Actually it would make sense to use this technique for NOR flash identically, as it would avoid one write access to the flash. Check out common/env_nand.c for details. Best regards Markus Klotzbuecher -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-0 Fax: +49-8142-66989-80 Email: [EMAIL PROTECTED] ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Register now and save $200. Hurry, offer ends at 11:59 p.m., Monday, April 7! Use priority code J8TLD2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ U-Boot-Users mailing list U-Boot-Users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/u-boot-users
