The MCP23X08EV and MCP23X17EV evaluation boards demonstrate the MCP23X08 and MCP23X17 devices in a simple I/O application. These boards include two switch selectable I/O expanders for evaluation of either the I²C or SPI devices. ICSP headers are located on the boards for easy access to the PIC10F202 and PIC16F818 devices. The jumpers and headers allow GPIO expanders to connect directly to a customer application without having to modify the boards.