8-bit I/O expander for I2C-bus, PCF8574 on board Overview The PCF8574 IO Expansion Board is used as remote 8-bit I/O expander for I2C-bus. Up to 8 PCF8574 IO Expansion Board can be connected to the I2C-bus, providing up to 64 I/O ports. The PCF8574 IO Expansion Board features I2C pinheader on one side, and I2C connector on the opposite side. Hence, it's more flexible to connect the board to your development system. The board also supports I2C cascading, allowing the use of multi module connected to the I2C bus at the same time by connecting the pinheader and connector. Features PCF8574, I2C interface, 8-bit parallel port Package Contains PCF8574 IO Expansion Board × 1 For more resources you may need, pls contact me via Amazon message, i will send you then via attachment.