User guide

RUGGEDCOM ROS
User Guide
Chapter 5
Setup and Configuration
Force Half-Duplex (HD) Operation Mode 125
The Device Address Table contains addresses and locations of devices configured (or learned) for specific
protocols.
If a protocol is configured to use TCP to transport data, the server will start listening to the IP Port configured for
the protocol. At the same time, TCP connections will be placed to all IP addresses where devices for that protocol
are attached. ROS will keep only one connection open to one IP Address on one IP Port.
Use of Differentiated Services Code Point (DSCP)
ROS has the ability to set the DS byte in the IP header of outbound IP packets. The value can be configured on
an ingress serial port, and/or for a protocol. Which value will be used depends on the protocol configured on a
port and the transport configured for the particular protocol.
UDP/IP transport supports a DSCP setting per serial port or per protocol. If a configuration contains a DSCP
setting per serial port as well as per protocol then the system will use whichever setting has a higher DSCP
value.
TCP/IP transport supports per protocol DSCP setting. RawSocket and Modbus Server protocol properties are
configured per port as well, so they always support DSCP setting per serial port.
Section 5.4.4
Force Half-Duplex (HD) Operation Mode
A force half-duplex mode of operation allows use of extensions to create echo loops, similar for example to an
optical loop topology that utilizes the RUGGEDCOM RMC20 repeat mode function.
NOTE
If a port is set to force half-duplex mode, all data received while data is being sent will be discarded. To
set this mode, the port must work natively in full-duplex mode.
The following illustrates a topology that utilizes the RMC20 repeat mode function.