The MCP23X08 device provides 8-bit, general purpose, parallel I/O expansion for I2C bus or SPI applications. The two devices differ in the number of hardware address pins and the serial interface:
• MCP23008 – I2C interface; three address pins
• MCP23S08 – SPI interface; two address pins
The MCP23X08 consists of multiple 8-bit configuration registers for input, output and polarity selection. The system master can enable the I/Os as either inputs or outputs by writing the I/O configuration bits. The data for each input or output is kept in the corresponding Input or Output register. The polarity of the Input Port register can be inverted with the Polarity Inversion register. All registers can be read by the system master.
The GPIO Expander Keypad and LCD Demo Board is designed to demonstrate the use of the MCP23S08/17 (SPI interface) and the MCP23008/17 (I2C interface) devices in a keypad and LCD example. The MCP23X17 (16-bit) devices interface to a 2x16 LCD module and the MCP23X08 (8-bit) devices interface to a 4x4 keyed matrix.
The MCP23X08 8-bit GPIO Expander Evaluation Board 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 PICkit™ Serial I2C Demo Board was designed to easily connect to the PICkit Serial Analyzer (DV164122). The PICkit Serial Analyzer provides the I2C master mode serial communications and power for the PICkit™ Serial I2C Demo Board. The devices on the demo board operate in the I2C slave mode and can easily be connected to virtually any demo or development board by connecting the...