A while ago I received a couple of I/O port expander modules that use the I 2 C protocol ... so there can be up to 16 of these I/O expanders PCF8574/74A together on the same I2C-bus, supporting up to ...

However, if you use an LCD module with I2C interface ... which is a general purpose bidirectional 8 bit I/O port expander that uses the I2C protocol. The PCF8574 is a silicon CMOS circuit provides ...