Interfacing NXT with I2C
The sensor ports on the NXT support a serial digital protocol called I2C, which was developed by Philips in the 1980’s for use in consumer electronics (in television sets, for example). This article describes the use of a simple I2C chip that provides 8 digital I/O ports with the NXT.Each one of these eight ports can be used as either input or output. These inputs and outputs are binary: they are either on or off.
   Interfacing NXT with I2C
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