[Wolves] EEprom corruption

[Wayne morris]

----- Original Message ----- 
From: "Simon Burke" <simon.burke at gmail.com>
To: "Wolverhampton Linux User Group" <wolves at mailman.lug.org.uk>
Sent: Monday, October 04, 2004 12:59 PM
Subject: Re: [Wolves] EEprom corruption


>>
>> Your mostly right, but afaik an eeprom can only be erased in an eraser, 
>> not
>> in the piece of kit it is fitted too.
>> Likewise can only be programmed by w programmer.
>> So if it is corrupted, it should be corrupted for good - ie the NIC will 
>> not
>> be able to reprog it.
>>
>> Different case if it is a flash prom.
>>
> Now the other question, how the ...heck did it get corrupted, I
> assumed something along the lines of a surge or something.

As far as I know, to program an EEprom, you apply a voltage to a pin that is 
not used in the device and then
apply the data via parallel pins in. So I guess an eprom could be 
'programmed' in situ if there was a problem with
the connections on the board to it, or via a surge causing internal 
shorting.

The other alternative is that the chip is not located in its socket/ dry 
joint if soldered in properly so that the data being read from it is
corrupt - rather than the eprom itself being bad.

Oh yes, sure its not a UV erasible eprom? Will have a window on the top 
covered by a sticker (to stop it being erased by sunlight).
>From my experience with these, its pretty damn hard to get them to lose data 
by sunlight, but it us theretically possible.

I have an eprom reader/programmer if you wanted to check the data on the 
chip.