Re: [EE] High reliability store and recall of data in EEPROM

You could use Reed-Solomon encoding, that way you would be able to 
detect errors of up to an arbitrary number of bits (you choose that 
number, depending on how many extra bits you can add to your data) and 
correct half that amount of wrong bits.


Cheers,

Isaac




Em 06/12/2024 18:49, David VanHorn escreveu:
> I have a need to store some data in non-volatile memory, with the caveat
> that corrupt data MUST NOT occur.  Things go "big badda boom" otherwise.
>
> Offhand, I came up with storing each byte as a four byte array (I have TONS
> of space available)
> If I'm storing 0x01 then it would look like this:
>
> 1       2        3       4
> 0x01, 0xFE, 0x01, 0x55
>
> Xor 1 and 2, result must be zero.
> Xor 3 and 2, result must be zero.
> compare 1 and 3 result must be zero (not sure this is needed)
> check 4, must be 0x55 otherwise a wild write has happened in EE.
> Finally the values allowed will be sparse, and likely only a single bit
> will be set, so I will check that the value I read is one of the allowable
> values.
>
> If any of those checks fails, we render safe and halt.
>
> Is there a more "rock solid" method?    What would be done in an automotive
> environment for something like throttle position?   What would be best
> practice for medical life safety?

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