Lpc2000

One has to consider what the purpose of EE_Demo is.  I see it as
providing an EEPROM interface for FLASH.  It is implied therefore,
that if you use this interface, you get EEPROM for free on the LPC. 
This IMO is not right.

The two technologies are different in that unlike FLASH, EEPROM is
*designed* for erase-and-write one byte at a time.  As a result, the
endurance of the system as a whole can be easily estimated directly
from EEPROM endurance.

In the case of FLASH emulation of EEPROM, the endurance of the system
quite different to FLASH endurance.  Minimum erase size (sector size)
and minimum write size (128-bits) needs to be taken into account in
the model to determine system endurance.

The EE_Demo hides this important consideration, hence my objection.

I have seen designs that work perfectly during prototype and initial
launch, but fail miserably in the field well ahead of their 'design'
lifetimes because these factors were not taken into account.  

The other thing to bear in mind in the case of LPC is that LPC native
flash endurance cycle is less than the ECC'ed endurance cycles that is
specified.

Jaya

--- In lpc2000@yahoogroups.com, "Bruce Paterson" <bruce.paterson@b...>
wrote:

> > I would like to add -- be careful about using flash as 
> > replacement for EEPROM.  It will work well for initial tests 
> > but it fails in the field because EEPROM and FLASH 
> > technologies have very difference endurance limits.
> > 
> > In this sense, as someone else said, the EE_Demo IMHO is an 
> > example of perfect demo -- works only for the purpose it was 
> > designed for but is of little or no use in real life otherwise.
> 
> I'll have to disagree here. Surely it depends very much on what you are
> using the Flash-EEprom *for*; that is, how often you write to it ?