The whole clock uses 16 individual, upright rotated 16×2 LCDs that are ... To communicate with each LCD via I2C, two TCA9548A I2C multiplexers are connected to an Arduino, along with an RTC ...

We like this approach because instead of doing some hard-core LCD work he’s using ... [Tech2077] grabbed an I2C port expander that uses just 2 of the RPi lines to address even lines of the ...