> Do you include a validation token
> such as a CRC or Cksum when writing
> records to an I2C EEProm device?

Steve is right, if hardware works good, there is no need for such validation. Collision detection would be enough (ie, you should verify every SCL and SDA state after trying to deassert them).

Since I usually don't do that (software verification makes data transfer incredibly slow), I had sometimes problems without software validation. For example, if SDA is shorted to the ground, you always get an ACK. All bits read from I2C will appear as zeroes. Then, if you use simple checksum, it will be always true :( Only CRC16 helped to solve this.

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Tomas