MCP23017-E/SP - 

The Microchip I/O Expander are 8- and 16-bit input/output expander designed to provide embedded systems with general-purpose remote I/O expansion through an IC™ and SPI serials port. The fully bi-directional I/Os default to inputs and can be configured as inputs or outputs. Additionally, there are multiple 8-bit registers that are programmable and provide for configuration (input or output control), output value, and polarity (active low or high).