Figure 14: Fast Ethernet with integrated magnetics reference schematic
2.3.1.3 Unused Ethernet Signals Termination
All unused Media Independent Ethernet signals can be left unconnected.
2.3.2 Reduced Gigabit Media-Independent Interface Ethernet Port
In addition to the Media Dependent Ethernet port, the Verdin family provides a second Ethernet
port in the "Reserved" category. However, this secondary port is provided as Reduced Gigabit
Media-Independent Interface (RGMII). This means only the Ethernet MAC (Medium Access Control)
is on the module. The PHY (physical layer) needs to be on the carrier board. This allows for
additional flexibility in choosing the suitable transport medium (e.g. fiber-optical cable).
Some of the Verdin modules additionally allow to use the interface as RMII (Reduced Media-
Independent Interface) for Fast Ethernet. For compatibility reasons, the RGMII is the preferred
interface for an Ethernet PHY on the carrier board.
The RGMII standard supports different I/O voltages. However, for the Verdin module family, the
preferred I/O voltage is 1.8V. This increases the compatibility between different Verdin modules.
Besides the RGMII, there is a Management Data Input/Output interface (MDIO) for managing the
PHY on the carrier board. Some Verdin modules maybe share the interface with the on-module
Ethernet PHY. In these cases, special care must be taken that the address of the carrier board PHY
does not conflict with the on-module PHY address.
2.3.2.1 RGMII Signals
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