Audriis level shifter cannot operate without reference voltages on both I2C buses. The effects are that no I2C communication is possible. If you look at the SDA and SCL lines with an oscilloscope, you can see decreasing voltages which result in incorrect transmission. This is not a bug of Audrii - this is really a feature! It allows you to connect Audrii to I2C systems with voltages from 1.2 to 5.5 Volt. That means that your system needs to supply the reference voltage as Audrii does NOT do this.
For example: On Main I2C you have connected Tracii 400. On Aux I2C you have connected your own I2C bus with 3.3V. In this case Tracii 400 can supply Main I2C with 5V if the appropiate jumpers on Tracii are set but you also must supply your 3.3V supply to the Aux I2C connector. Itīs as simple as that.
