The PCF8574T IO Expansion Board is an I2C-bus remote 8-bit I/O expander. The I2C-bus can be connected to up to 8 PCF8574T IO Expansion Boards, providing up to 64 I/O ports. The PCF8574T IO Expansion Board includes the ability to connect multiple modules to the I2C bus at the same time by connecting the pinheader and connector. Onboard is a small potentiometer for adjusting the backlight of the LCD1602 or LCD2004, as well as a jumper cap for controlling the LED light switch.
