The DCMAC Subsystem features a MAC interface (MAC I/F) which permits the user logic to bypass the PHY logic and directly access the internal hardened time-sliced MAC resources of the DCMAC Subsystem.
The MAC I/F can be used only when the DCMAC Subsystem is configured in Independent MAC and PCS+FEC mode. This mode is selected using the control field ctl_tx_independent_tsmac_and_phy_mode of the GLOBAL_MODE register. This field is configured statically when there is no data flowing through the DCMAC Subsystem.
The MAC I/F provides up to 600 Gb/s of bandwidth. You might choose to scale the clock frequency to meet the requirements of a given application. Some representative examples are shown in the following table.
MAC I/F Bandwidth | MAC I/F Clock Frequency (MHz) |
---|---|
200 Gb/s | 130.208 |
300 Gb/s | 195.313 |
400 Gb/s | 260.417 |
600 Gb/s | 390.625 |