The PCF8574 I / O expansion card is used as an 8-bit remote I / O expansion for the I2C bus. Up to 8 PCF8574 I / O expansion cards can be connected to the I2C bus, providing up to 64 I / O ports.
The PCF8574 IO expansion card has an I2C header on one side and an I2C connector on the other side. Therefore, it is more flexible to connect the board to your development system. The board also supports the I2C cascade, allowing the use of multiple modules connected to the I2C bus at the same time by connecting the pinheader and connector.
