The first board to connect to the expansion board - Input Board

Technical Specs :

• Input Volatge : 3V3 or 5V.
• Digital Input : 16.
• All entries remain logic high level with the 10K ohms pull-up resistor. When shorting the input terminals (protected with a diode in series) the logic level change to low.
• Interface with the Arduino : MCP23S17 (SPI Bus).
• Programable interrupts : 2.
• Lenght : 68.58 mm.
• Widht :  62.23 mm.

Schema

Simulation

Prototype