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Auto MDI/MDI-X Connection
The Auto MDI/MDI-X function allows users to connect the Moxa CSM-200’s
10/100BaseTX ports to any kind of Ethernet device, without needing to
determine the type of Ethernet cable being used for the connection.
This means that you can use either a straight-through cable or cross-over cable
to connect the CSM-200 Series to Ethernet devices.
Dual Speed Functionality and
Switching
The Moxa CSM-200’s 10/100 Mbps RJ45 Ethernet port auto negotiates with
the connected device for the fastest data transmission rate supported by both
devices. All models of the CSM-200 Series are plug-and-play devices, so that
software configuration is not required at installation, or during maintenance.
The half/full duplex mode for the RJ45 Ethernet ports is user dependent and
changes (by auto-negotiation) to full or half duplex, depending on which
transmission speed is supported by the attached device.
Auto-Negotiation and Speed Sensing
All of the CSM-200’s RJ45 Ethernet ports independently support
auto-negotiation for 10BaseT and 100BaseTX transmission speeds, with
operation according to the IEEE 802.3u standard.
This means that some nodes could be operating at 10 Mbps, while at the same
time other nodes are operating at 100 Mbps.
Auto-negotiation takes place when an RJ45 cable connection is made, and then
each time a LINK is enabled. Moxa’s CSM-200 advertises its capability for
using either 10 Mbps or 100 Mbps transmission speeds, with the device at the
other end of the cable expected to advertise similarly. Depending on what type
of device is connected, this will result in agreement to operate at a speed of
either 10 Mbps or 100 Mbps.
If a Moxa CSM-200 RJ45 Ethernet port is connected to a non-negotiating
device, it will default to 10 Mbps speed and half-duplex mode, as required by
the IEEE 802.3u standard.