The DCMAC Subsystem features a MAC interface (MAC I/F) that 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 ctl_tx_independent_tsmac_and_phy_mode control field 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 Gbps of bandwidth. Scale the clock frequency to meet the requirements of a given application. The following table shows some representative examples.
| MAC I/F Bandwidth | MAC I/F Clock Frequency (MHz) |
|---|---|
| 200 Gbps | 130.208 |
| 300 Gbps | 195.313 |
| 400 Gbps | 260.417 |
| 600 Gbps | 390.625 |