thanks for the reply Australia
the comment about 6 bytes was there from the slave writer example code originally, which i guess is the 5 charachters hello plus a space. I dont fully understand C++. I need to figure out how to pass the ping data to wire.write(). Originally i was trying to figure out how to read the Ping sensor attached to Arduino in LabView; still working on that as well, thats how I came across I2C and thought how useful it would be for networking sensors around the lab. Any ideas most appreciated. Thank you arduino forum
About my project: I use the Parallax Ultrasonic(ping) sensor to measure wave heights and wave profiles in my wavepool; heights from 4 cm. - 12 cm. the sensor works fine and i'm able to read the data into console or processing, and if I tab space the data and copy it from the console I can import it into labview. If interested you can see Arduino running my wavepool on youtube; Arduino + wavepool + nxt, or username runman69. I use Arduino's pwm to control a motor that opens and closes the valve the holds and releases the wave; higher value of pwm makes the valve open and close quicker and hence loading less water and making smaller wave, shorter pwm means longers load time and bigger wave.