The transmit MAC I/F allows the user logic to directly monitor the time-sliced MAC transmit datapath. The interface is time-sliced and is composed of 24 x 66-bit blocks supporting up to 600 Gb/s bandwidth for up to 40 channels. In this operating mode, the PCS encode function is included in the DCMAC transmit datapath.
The user logic can use the TX MAC I/F as an observation point for a multi-channel MAC that accepts packets on the channelized TX AXI4-Stream interface. In a Flex Ethernet (FlexE) application, the user logic might choose to connect the TX MAC I/F to a transmit FlexE Shim (FlexE multiplexer).