Moxa CSM-200-1218 [7/9] Auto mdi mdi x connection

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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.