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Re: REG: FLASH BLOCK LOCKING



Block locking can be used to prevent accidental erasure, but bear in mind that
you usually need to jump through a few hoops to disable the locking again. 
Protection is after all the whole purpose of the scheme.  In some cases, a
higher voltage have to be applied to the chip to allow unlocking.  This may
require special hardware or even the removal of the chip and unlocking in a
PROM burner. Locking blocks will also upset the JFFS code when it tries to
recover a dirty sector or write to a locked block.  Each manufacturer tends
to have their own locking scheme, even when the chips are otherwise
identical.

Cheers,

Herman

On Wed, 29 Aug 2001, Ashok M Padmanaban wrote:
> 
> Hi,
> Are there any methods by which portions of  falsh device can be locked,
> so that accidental erase or corruption can be avoided.
> If there are, what are those.
> Are there any temporary and permanent locking mechanism.
> 
> In 3 volt intel strataFlash memory 28F128J3A, a block locking
> scheme is provided with BLOCK LOCK-BITS.
> How can these bits be used to lock the flash blocks.?
> If  blocks are locked , does this mean that accross the power cycles
> this will be consistent.
> 
> regards
> ashok
> 
> 

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-- 
Herman Oosthuysen
Phone: 403+569-5687, Fax: 403+235-3965
E-mail: Herman@xxxxxxx.com 
Web: http://www.WirelessNetworksInc.com
Wireless Networks Inc.
#300, 3016 5th Ave NE, 
Calgary, Alberta, T2A 6K4, 
Canada.


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