The MCP23X08EV is an evaluation board for MCP23X08 8bit GPIO expander, which demonstrates simple input/output functionality of the MCP23008 I2C interface and the MCP23S08 SPI interface. The system demonstrates the simplicity of monitoring four inputs and applying the level to associated outputs. The evaluation board designed to demonstrate simple, low cost input/output expansion using the MCP23X08 devices and a 6 pin PIC10F202 microcontroller. Four MCP23X08 pins are configured as inputs and four as outputs. When an input level is changed, the associated output pin is driven to the same level. This is accomplished by the MCU reading the input pins and writing the appropriate value to the output pins. The MCP23X08 are provided in small, space saving 20 lead SSOP packages. Adding the small 6 lead PIC10F202 device in a SOT 23 package makes for small overall PCB area.