The TCA9548A adapter is connected to an I2C device with multiple identical addresses on the same I2C port on the main control board for normal communication and use. There are 8 I2C interfaces on one expander, and there are eight bidirectional transfer switches that can be controlled by I2C Bus. This means that after transferring an expansion module, 8 identical addresses can be connected to the same I2C port. When the 8-channel expansion board device is also used normally, the default address of this expander is 0x70, the address can be changed and can be set between 0x70 ~ 0x77 according to your needs. In theory, 8 expansion modules can be cascaded in the address 0x70 ~ 0x77, and each expansion module can connect 8 devices with the same address. This realizes the same I2C port and connects 64 devices with the same address and uses them normally. TCA9548A expansion board compatible with IIC bus and system management bus (SMBus), active low reset input, support hot plug, low standby