How to connect the Arduino Uno with the expansion board : The Expansion bridge.

The expansion bridge is an Arduino Shield that connect the Arduino UNO with the expansion board.

 

Simulation

 Technical specifications

 - Independent +5V for the expansion board.
 - Independent +3V3 for the expansion board.
 - Real time clock DS1307.
 - Level converter to adapt the voltage in case of use Arduino Zero (+3V3).

Schema