There is plenty of power to do atleast 100 feet of wire between each calc... Grant >Yes, well, it depends on distance and everything... if you want to >broadcast to like 5 calcs, that are 10 - 20 feet away, then I don't >think there is enough power to do it... is there? (Aren't the pulses >5V?) And if there isn't, I2C bus extenders are $2.50.