Chapter 3: Configuration
Page 12 724-746-5500 | blackbox.com LMC5601C-VDSL2
3.10 Forcing the Data Port Speed
The DATA port can be manually configured on HDMCII VDSL2 LAN
Extender Module (Extended Temp) for 10 Mbps or 100 Mbps operation.
Before manually setting the speed, disable Auto Negotiation (Set DIP Switch
#5 to the OFF position.)
• 10 Mbps for the DATA port is configured by setting DIP Switch #9 to the
OFF position (default).
• Configure the DATA port for 100 Mbps operation by setting DIP Switch
#9 to the ON position.
3.11 Flow Control
Flow Control is used as back pressure on the 10/100BaseT DATA interface
to avoid dropping packets during VDSL link congestion. Full-Duplex Flow
Control will be advertised only when the module is set to Full-Duplex Mode.
For Full-Duplex Flow Control to operate, the link partner (connected devices)
must also support Flow Control. Half-Duplex Flow Control does not
advertise but provides a hardware based backpressure on the Ethernet line
to limit traffic.
Flow Control should be considered whenever the VDSL line provides less
bandwidth than the DATA port. If the Ethernet line is attempting to send
more data than the VDSL2 line can support, the Overflow (OVF) LED will
come ON indicating frames are being discarded due to congestion.
Overflow activity will be less if Flow Control is enabled. Flow Control or
Pause will limit the number of dropped Ethernet frames by reducing the
congestion, therefore minimizing the overflow of the VDSL line.
Configure the DATA port on the HDMCII VDSL2 LAN Extender Module
(Extended Temp) for Flow Control by setting DIP Switch #6 to the ON
position.
