The I2C MUX is made from two TCA9548 I2C multiplexers. In Sayma AMC there are two main I2C buses: MMC_I2C and FPGA_I2C. Each of them is connected to one multiplexer. Outputs are tied together, so masters (MMC and FPGA) can access to any of 7 I2C buses. Addidtionaly MMC has access to FPGA_I2C and is connected to IPMB through AMC connector.