Peter, it seems to me that the initial question is fogotten: I was looking for a protocol better than I2C. If you want to discuss the use of I2C, I'm in your disposition, but it's another question, and we could do it in private correspondence because it seems to me that we have a long road to do to arrive to a common point of view. Probably, it could be boring for other participants. I send you a private letter shortly. Anyhow, thank you for your participation.
Michael.