Hardware Reference Guide
IP67 Industrial Ethernet Switches
26
Switch Features
© Woodhead Software & Electronics, a division of Molex
Document Edition: 1.1, Document # 715-5000
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Back Pressure for Half-Duplex
The switches will apply “back pressure” when necessary with half-duplex operation. This
will reduce congestion on busy networks.
Buffering
SRAM is used for buffering the messages. The DRL-750 has an internal 512 Kbit SRAM for
buffering, and the DRL-78x have 1 Mbit.
Unmanaged Operation
The switches require no supervisory processor to operate properly.
Flow Control
The switches automatically support flow control frames on both transmit and receive sides.
Forwarding
The switches support store and forward mode. They forward messages with known addresses
out the appropriate port only. Messages with unknown addresses, broadcast messages, and
multicast messages get forwarded out all ports, except the source port. The switches will not
forward error packets, 802.3x pause frames, or “local” packets.
Full/half-Duplex Operation
The switches’ ports support both full and half duplex flow control.
Illegal Frames
Illegal frames, as defined by IEEE 802.3, will be dropped. This includes short frames, long
frames and FCS error frames.
