SPRUII0F May 2019 – June 2024 TMS320F28384D , TMS320F28384D-Q1 , TMS320F28384S , TMS320F28384S-Q1 , TMS320F28386D , TMS320F28386D-Q1 , TMS320F28386S , TMS320F28386S-Q1 , TMS320F28388D , TMS320F28388S
Ethernet IEEE802.3 specified MII interface is supported with possible minor variation in clocking to optimize the clock delay to operate the Tx FIFO. Unlike regular integration of Tx clock being sourced by the PHY, the ESC implementation allows the common source clock between PHY and ESC be used for Tx logic. The option is selected by manual Tx shift compensation which allows Tx-Data and Tx-En be compensated in steps of 10 ns to meet the timing requirements of data sampling at the PHY.
The following signals are used by the ESC to connect to an Ethernet PHY. The MDIO pins are not shown in Figure 31-4, as these pins are covered in the next section.
The MII signals TX_ERR, COL and CRS are not used by the ESC. These are not available on the MCU for EtherCAT.
If an ESC MII interface is not used, LINK_MII has to be tied to the logic value high that indicates no link. RX_CLK, RXD, RX_ER, and especially RX_DV are connected to GND and this is taken care of by design internally when the functional IO mux for the RX pins is not configured when the IP is out of reset. The TX outputs can be left unconnected, by not configuring the Functional IO mux for respective EtherCAT functionality, unless the TX outputs are used for ESC configuration.