[U-Boot-Users] why eeprom vs flash

[Wolfgang Denk]

In message <47B48CD0.9060600 at ovro.caltech.edu> you wrote:
>
> I would imagine some designers prefer saving these type
> of parameters to an EEPROM, independent of the application
> (bootloader, kernel, filesystem, etc) flash. This would

Most of the designes I've seen so far then decided to use the  EEPROM
to  store  the  U-Boot environment, because then they didn't need any
special code to maintain the MAC addresses in  EEPROM.  That's  avery
bad decision, of course.

> So, as the designer, its up to you. But keep in mind that
> you want to make it hard for a customer to screw up, so
> a separate EEPROM could be a good choice.

In many cases it ain't. I've seen many board which lost their  EEPROM
contents,  typically because of edge condition problems as documented
in the file mentioned before - a poor power supply with too slow rise
times of the voltages makes an excellent test case. I know of systems
where it blows the EEPROM content in 2 out of 3 boot cycles :-(

Best regards,

Wolfgang Denk

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