
RTL8316
2001/11/09
Rev.1.72
15
6.18 Force Mode Setting of Port ability
The RTL8316 supports Duplex/Speed/Flow Control ability force mode setup on two ports. The two ports are Port[14] and
Port[15]. Each port has 4 force setting pins EnForceMode, ForceDUPLEX, ForceSPEED and ForceFCTRL. For each port,
EnForceMode = 1 indicates the force mode has been enabled on the corresponding port. The corresponding port of the
RTL8316 will use the duplex, speed and flow control ability as these pins are set. Furthermore, the RTL8316 will write the
DUPLEX and SPEED to bit 13 and bit 8 of PHY’s register 0, and bit 12 of register 0 will be written to be '0' to enable the
corresponding PHY port to act at force mode. It will then continue to poll the port link status from the SMI.
6.19 Port Based HOME VLAN Function
Port based HOME VLAN function is supported by the RTL8316. The VLAN function is controlled by pin "ENVLAN" during
h/w reset. When ENVLAN ='1', the VLAN function is enabled and the system is configured as 14 VLANs +2 overlapping
ports or 15 VLANs +1 overlapping port topology. That is, for 14 VLANs + 2 overlapping ports topology, each port of
port#0~13 is configured as an independent VLAN, and all these 14 VLANs share the same overlapping ports: port#14,15. For
15 VLANs + 1 overlapping port topology, each port of port#0~14 is configured as an independent VLAN, and all of these 15
VLANs share the same overlapping port: port#15.
For VLAN packet forwarding (ex. 14VLANs +2 overlapping ports): Any unicast/broadcast packet received from ports #0~13
can only be forward to the overlapping ports, if the destination port belongs to another VLAN, the packet will be discarded. If
the source port is an overlapping port (port #14,or #15), then the frame can be forward to any destination port. This 14 VLANs
or 15 VLANs topology is useful to allow home networks to share a common server or router, but be configured as different
VLANs for security reasons.
Security HOME VLAN application diagram