The operation of the core remains unchanged. When operating at a speed of 10 Mbps, every byte of the MAC frame (from preamble to the frame check sequence field, inclusive) is repeated for 100 clock periods to achieve the desired bit rate. Only when the core is connected to Ethernet MAC peripherals of the processing subsystem present in Zynq and Versal devices, the core will take care of converting the 8 bit from the core to 4-bit MII interface. In other cases, it is the responsibility of the client logic (for example, an Ethernet MAC) to sample this data correctly.