This breakout board based on the Texas Instruments TCA9548A 8-channel I2C switch provides a way to get up to 8 same-address I2C devices hooked up to one microcontroller Ò this multiplexer acts as a gatekeeper, shuttling the commands to the selected set of I2C pins with your command. The multiplexer itself is on I2C address 0x70 (but can be adjusted from 0x70 to 0x77) and you simply write a single byte with the desired multiplexed output number to that port. In theory, you could have 8 of these multiplexers on each of 0x70-0x77 addresses in order to control 64 of the same-I2C-addressed-part.