Tamas,

On Wed, 3 Oct 2007 16:41:06 +0100, Tamas Rudnai wrote:

> Hi,
> 
> Could it be as a result of some kind of testing methods they using (like I
> do not know, writing the flash several times with some patterns) and then
> with these they forgot to erase?

I don't think they forgot!  :-)  Thinking about it, I suspect that the manufacture/test process for most chips ends with a bulk erase, but in the case of the '88 (and 
maybe others) the final stage is a write of all zeros and a read-back.  We're used to chips being supplied erased because for UV erasable or OTP chips there's no 
other way,  but for EEPROM (/flash) there's no real reason why they should be - as long as the user knows that they have to do a bulk erase before programming, 
it's not a problem.  Of course, if they used to be erased but now something has changed, it could disrupt a manufacturing process that assumed they were erased 
and didn't cater for doing so itself, but I haven't seen any complaints like this.

Cheers,


Howard Winter
St.Albans, England


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