I²C Bus Repeater
The smartHub features an I²C bus repeater to ensure good quality of I²C signals.
Long cables increase capacitance, making the bus more prone to data error. A repeater allows the I²C bus to be extended, without degradation of performance even during level shifting.
I tested different solutions from NXP and TI intensively. I discarded most of the repeaters as they weren't compatible with the RoboTX or failed to protect the I²C bus from interferences.
The smartHub doesn't require any command to work.
Finalised and Working Hub
The smartHub was built directly, thanks to prior tests with I²C repeaters and hubs.
In the model pictured, the I²C cables sum more than 1 metre long in a dense and heavily polluted environment, due to the proximity of many motors and solenoids.
The I²C slave devices are (clockwise, from top left) :
No data loss was reported.