On 13 Dec 2017 at 12:13, Isaac M. Bavaresco wrote:

> I think you are overthinking it.
>=20
> The usual way of doing things is to calculate the CRC before writing the
> data and writing the entire record at once, data and CRC. As you are
> using EEPROM, it is possible to write the CRC first, so if a write is
> aborted midways then there is no possibility of having data without a
> CRC in the memory. Or simply put the CRC in the beginning of the record.
>=20
> Think of a block memory device (FLASH, diskette of hard disk drives),
> each block or sector must be written in a single operation.
>=20
> If you do things this way then your concern becomes a lot less important.
>=20
> It is always possible for a memory corruption to alter data and CRC at
> the same time and make a corrupted record to appear OK, but it is highly
> improbable.
>=20
> One measure that I think is easy to implement and adds a lot of security
> is avoiding sequence number 0xffff.

I think you are right, I have been over thinking it. Will simplify my appro=
ach,=20
implement it, test it, and let you know the result. Many thanks for your in=
put.

--=20
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