I want to connect a Wii nunchuck to my Arduino. Since the Arduino is running at 5V, and the nunchuck at 3.3V, I think I need to convert the SDA/SCL levels. Stepping them down to 3.3V should be relatively straightforward (voltage divider), but how do I make this bidirectional?
I have seen bus transceivers such as the SN74LVC245A, which would do the job, but seem to rely on being told which direction to do the conversion in. Is this normal? Presumably in my case, I'd tell it A->B for sending, and B->A for receiving, but taking that approach I'd lose another pin. Is there a better component/schematic for doing this?