4RF Aprisa SR+ - Page 187

Managing the Radio | 187
Aprisa SR+ User Manual 1.11.1
Serial Port
This parameter selects the serial port to use IP terminal server.
Option
Function
Serial Port
This is the normal RS-232 serial ports provided with the RJ45
connector.
USB Serial Port
This is the optional RS-232 / RS-485 serial port provided with the
USB host port connector with a USB to RS-232 / RS-485 RJ45
converter cable (see ‘USB RS-232 / RS-485 Serial Port’ on page
434).
Mode
This parameter defines the mode of operation of the terminal server connection. The default setting is
Client and Server.
Option
Function
Client
The radio will attempt to establish a TCP connection with the
specified remote unit. Generally, this setting is for the base station
with an Ethernet connection to the SCADA master.
Server
The radio will listen for a TCP connection on the specified local
port. Generally, this setting is for the remote radio with a serial
connection to the RTU.
Data received from any client shall be forwarded to the associated
serial port while data received from that serial port shall be
forwarded to every client with an open TCP connection.
If no existing TCP connections exist, all data received from the
associated serial port shall be discarded.
Client and Server
The radio will listen for a TCP connection on the specified local
port and if necessary, establish a TCP connection with the
specified remote unit. Generally, this setting is used for the
remote radio but it should be used carefully as two connections
might be established with the base station.
Data received from any client shall be forwarded to the associated
serial port while data received from that serial port shall be
forwarded to every client with an open TCP connection.
Inactivity Timeout (seconds)
This specifies the duration (in seconds) to automatically terminate the connection with the remote TCP
server if no data has been received from either the remote TCP server or its associated serial port for the
duration of the configured inactivity time.
TCP Keep Alive
A TCP keep alive is a message sent by one device to another to check that the link between the two is
operating, or to prevent the link from being broken.
If the TCP keep alive is enabled, the radio will be notified if the TCP connection fails.
If the TCP keep alive is disabled, the radio relies on the Inactivity Timeout to detect a TCP connection
failure. The default setting is disabled.
Note: An active TCP keep alive will generate a small amount of extra network traffic.