1. The TCA9548A adapter is connected for normal communication and use with an I2C device with multiple identical addresses on the same I2C port on the main control board. There are 8 I2C interfaces on one expander, and there are eight bidirectional transfer switches that can control the I2C bus. This means that after connecting 1 expander, 8 identical addresses can be connected to the same I2C port. 2. When the 8channel expansion card device is also used normally, the default address of this expander is 0x70, and the address can be changed and adjusted between 0x70 and 0x77 as needed. Theoretically, 8 expanders can be cascaded in the addresses 0x700x77, and each expander can connect 8 devices to the same address. This enables the same I2C port to connect 64 devices with the same address and use them normally. 3. Expansion card TCA9548A, compatible with IIC bus and system management bus (SMBus), has an active low reset input, supports hot insertion, has low standby current, no interference when switched on, and supports voltage level shift between 1.8 V, 2.5 V, 3.3 V and 5 V. It is a TCA9548A I2C IIC multiplexer breakout board. Depending on the content of the programmable control register, each individual SCn/SDn channel or a combination of channels can be selected. 4. If a timeout or other faulty operation occurs, the system master can reset the TCA9548A by setting the /RESET input to Low. Similarly, a poweron reset selects all channels and initializes the I2C/SMBus condition machine. Reset and initialization can also be achieved by activating /reset, and there is no need to turn off the part.